mirror of
https://github.com/holub/mame
synced 2025-06-03 11:26:56 +03:00
1309 lines
48 KiB
C
1309 lines
48 KiB
C
/*
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TX-0 emulator
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Two variants:
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* initial model 64kWord RAM
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* later model 8kWord RAM
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Raphael Nabet 2004
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*/
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#include "emu.h"
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#include "debugger.h"
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#include "tx0.h"
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#define LOG 0
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#define LOG_EXTRA 0
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static void execute_instruction_64kw(device_t *device);
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static void execute_instruction_8kw(device_t *device);
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static void pulse_reset(device_t *device);
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/* TX-0 Registers */
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struct tx0_state
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{
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const tx0_reset_param_t *iface;
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/* processor registers */
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int mbr; /* memory buffer register (18 bits) */
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int ac; /* accumulator (18 bits) */
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int mar; /* memory address register (16 (64kW) or 13 (8kW) bits) */
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int pc; /* program counter (16 (64kW) or 13 (8kW) bits) */
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int ir; /* instruction register (2 (64kW) or 5 (8kW) bits) */
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int lr; /* live register (18 bits) */
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int xr; /* index register (14 bits) (8kW only) */
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int pf; /* program flags (6 bits expandable to 10) (8kW only) */
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/* operator panel switches */
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int tbr; /* toggle switch buffer register (18 bits) */
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int tac; /* toggle switch accumulator (18 bits) */
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int tss[16]; /* toggle switch storage (18 bits * 16) */
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unsigned int cm_sel : 16; /* individual cm select (1 bit * 16) */
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unsigned int lr_sel : 16; /* individual lr select (1 bit * 16) */
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unsigned int gbl_cm_sel : 1;/* global cm select (1 bit) */
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unsigned int stop_cyc0 : 1; /* stop on cycle 0 */
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unsigned int stop_cyc1 : 1; /* stop on cycle 1 */
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/* processor state flip-flops */
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unsigned int run : 1; /* processor is running */
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unsigned int rim : 1; /* processor is in read-in mode */
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unsigned int cycle : 2; /* 0 -> fetch */
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/* 1 -> execute (except for taken branches) */
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/* 2 -> extra execute cycle for SXA and ADO */
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unsigned int ioh : 1; /* i-o halt: processor is executing an Input-Output Transfer wait */
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unsigned int ios : 1; /* i-o synchronizer: set on i-o operation completion */
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/* additional emulator state variables */
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int rim_step; /* current step in rim execution */
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int address_mask; /* address mask */
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int ir_mask; /* IR mask */
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int icount;
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legacy_cpu_device *device;
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address_space *program;
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};
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INLINE tx0_state *get_safe_token(device_t *device)
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{
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assert(device != NULL);
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assert(device->type() == TX0_64KW ||
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device->type() == TX0_8KW);
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return (tx0_state *)downcast<legacy_cpu_device *>(device)->token();
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}
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#define READ_TX0_18BIT(A) ((signed)cpustate->program->read_dword((A)<<2))
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#define WRITE_TX0_18BIT(A,V) (cpustate->program->write_dword((A)<<2,(V)))
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#define io_handler_rim 3
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#define PC cpustate->pc
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#define IR cpustate->ir
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#define MBR cpustate->mbr
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#define MAR cpustate->mar
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#define AC cpustate->ac
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#define LR cpustate->lr
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#define XR cpustate->xr
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#define PF cpustate->pf
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#define ADDRESS_MASK_64KW 0177777
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#define ADDRESS_MASK_8KW 0017777
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#define INCREMENT_PC_64KW (PC = (PC+1) & ADDRESS_MASK_64KW)
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#define INCREMENT_PC_8KW (PC = (PC+1) & ADDRESS_MASK_8KW)
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static int tx0_read(tx0_state *cpustate, offs_t address)
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{
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if ((address >= 16) || (cpustate->gbl_cm_sel) || ((cpustate->cm_sel >> address) & 1))
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/* core memory (CM) */
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return READ_TX0_18BIT(address);
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else if ((cpustate->lr_sel >> address) & 1)
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/* live register (LR) */
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return LR;
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/* toggle switch storage (TSS) */
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return cpustate->tss[address];
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}
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static void tx0_write(tx0_state *cpustate, offs_t address, int data)
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{
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if ((address >= 16) || (cpustate->gbl_cm_sel) || ((cpustate->cm_sel >> address) & 1))
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/* core memory (CM) */
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WRITE_TX0_18BIT(address, data);
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else if ((cpustate->lr_sel >> address) & 1)
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/* live register (LR) */
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LR = data;
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else
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/* toggle switch storage (TSS) */
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/* TSS is read-only */
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;
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}
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static void tx0_init_common(legacy_cpu_device *device, device_irq_acknowledge_callback irqcallback, int is_64kw)
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{
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tx0_state *cpustate = get_safe_token(device);
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/* clean-up */
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cpustate->iface = (const tx0_reset_param_t *)device->static_config();
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cpustate->address_mask = is_64kw ? ADDRESS_MASK_64KW : ADDRESS_MASK_8KW;
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cpustate->ir_mask = is_64kw ? 03 : 037;
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cpustate->device = device;
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cpustate->program = &device->space(AS_PROGRAM);
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}
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static CPU_INIT( tx0_64kw )
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{
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tx0_init_common(device, irqcallback, 1);
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}
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static CPU_INIT( tx0_8kw)
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{
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tx0_init_common(device, irqcallback, 0);
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}
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static CPU_RESET( tx0 )
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{
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tx0_state *cpustate = get_safe_token(device);
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/* reset CPU flip-flops */
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pulse_reset(device);
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cpustate->gbl_cm_sel = 1; /* HACK */
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}
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/* execute instructions on this CPU until icount expires */
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static CPU_EXECUTE( tx0_64kw )
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{
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tx0_state *cpustate = get_safe_token(device);
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do
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{
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debugger_instruction_hook(device, PC);
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if (cpustate->ioh && cpustate->ios)
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{
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cpustate->ioh = 0;
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}
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if ((! cpustate->run) && (! cpustate->rim))
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cpustate->icount = 0; /* if processor is stopped, just burn cycles */
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else if (cpustate->rim)
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{
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switch (cpustate->rim_step)
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{
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case 0:
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/* read first word as instruction */
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AC = 0;
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if (cpustate->iface->io_handlers[io_handler_rim])
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(*cpustate->iface->io_handlers[io_handler_rim])(device); /* data will be transferred to AC */
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cpustate->rim_step = 1;
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cpustate->ios = 0;
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break;
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case 1:
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if (! cpustate->ios)
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{ /* transfer incomplete: wait some more */
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cpustate->icount = 0;
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}
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else
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{ /* data transfer complete */
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cpustate->ios = 0;
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MBR = AC;
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IR = MBR >> 16; /* basic opcode */
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if ((IR == 2) || (IR == 1)) /* trn or add instruction? */
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{
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PC = MBR & ADDRESS_MASK_64KW;
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cpustate->rim = 0; /* exit read-in mode */
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cpustate->run = (IR == 2) ? 1 : 0; /* stop if add instruction */
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cpustate->rim_step = 0;
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}
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else if ((IR == 0) || (IR == 3)) /* sto or opr instruction? */
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{
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MAR = MBR & ADDRESS_MASK_64KW;
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cpustate->rim_step = 2;
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}
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}
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break;
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case 2:
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/* read second word as data */
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AC = 0;
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if (cpustate->iface->io_handlers[io_handler_rim])
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(*cpustate->iface->io_handlers[io_handler_rim])(device); /* data will be transferred to AC */
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cpustate->rim_step = 3;
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cpustate->ios = 0;
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break;
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case 3:
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if (! cpustate->ios)
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{ /* transfer incomplete: wait some more */
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cpustate->icount = 0;
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}
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else
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{ /* data transfer complete */
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cpustate->ios = 0;
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tx0_write(cpustate, MAR, MBR = AC);
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cpustate->rim_step = 0;
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}
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break;
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}
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}
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else
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{
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if (cpustate->cycle == 0)
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{ /* fetch new instruction */
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MBR = tx0_read(cpustate, MAR = PC);
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INCREMENT_PC_64KW;
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IR = MBR >> 16; /* basic opcode */
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MAR = MBR & ADDRESS_MASK_64KW;
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}
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if (! cpustate->ioh)
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{
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if ((cpustate->stop_cyc0 && (cpustate->cycle == 0))
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|| (cpustate->stop_cyc1 && (cpustate->cycle == 1)))
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cpustate->run = 0;
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execute_instruction_64kw(device); /* execute instruction */
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}
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cpustate->icount --;
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}
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}
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while (cpustate->icount > 0);
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}
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/* execute instructions on this CPU until icount expires */
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static CPU_EXECUTE( tx0_8kw )
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{
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tx0_state *cpustate = get_safe_token(device);
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do
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{
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debugger_instruction_hook(device, PC);
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if (cpustate->ioh && cpustate->ios)
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{
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cpustate->ioh = 0;
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}
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if ((! cpustate->run) && (! cpustate->rim))
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cpustate->icount = 0; /* if processor is stopped, just burn cycles */
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else if (cpustate->rim)
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{
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switch (cpustate->rim_step)
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{
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case 0:
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/* read first word as instruction */
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AC = 0;
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if (cpustate->iface->io_handlers[io_handler_rim])
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(*cpustate->iface->io_handlers[io_handler_rim])(device); /* data will be transferred to AC */
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cpustate->rim_step = 1;
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cpustate->ios = 0;
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break;
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case 1:
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if (! cpustate->ios)
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{ /* transfer incomplete: wait some more */
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cpustate->icount = 0;
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}
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else
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{ /* data transfer complete */
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cpustate->ios = 0;
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MBR = AC;
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IR = MBR >> 13; /* basic opcode */
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if ((IR == 16) || (IR == 8)) /* trn or add instruction? */
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{
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PC = MBR & ADDRESS_MASK_8KW;
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cpustate->rim = 0; /* exit read-in mode */
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cpustate->run = (IR == 16) ? 1 : 0; /* stop if add instruction */
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cpustate->rim_step = 0;
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}
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else if ((IR == 0) || (IR == 24)) /* sto or opr instruction? */
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{
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MAR = MBR & ADDRESS_MASK_8KW;
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cpustate->rim_step = 2;
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}
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}
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break;
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case 2:
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/* read second word as data */
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AC = 0;
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if (cpustate->iface->io_handlers[io_handler_rim])
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(*cpustate->iface->io_handlers[io_handler_rim])(device); /* data will be transferred to AC */
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cpustate->rim_step = 3;
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cpustate->ios = 0;
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break;
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case 3:
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if (! cpustate->ios)
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{ /* transfer incomplete: wait some more */
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cpustate->icount = 0;
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}
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else
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{ /* data transfer complete */
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cpustate->ios = 0;
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tx0_write(cpustate, MAR, MBR = AC);
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cpustate->rim_step = 0;
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}
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break;
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}
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}
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else
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{
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if (cpustate->cycle == 0)
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{ /* fetch new instruction */
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MBR = tx0_read(cpustate, MAR = PC);
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INCREMENT_PC_8KW;
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IR = MBR >> 13; /* basic opcode */
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MAR = MBR & ADDRESS_MASK_8KW;
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}
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if (! cpustate->ioh)
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{
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if ((cpustate->stop_cyc0 && (cpustate->cycle == 0))
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|| (cpustate->stop_cyc1 && (cpustate->cycle == 1)))
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cpustate->run = 0;
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execute_instruction_8kw(device); /* execute instruction */
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}
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cpustate->icount -= 1;
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}
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}
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while (cpustate->icount > 0);
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}
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static CPU_SET_INFO( tx0 )
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{
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tx0_state *cpustate = get_safe_token(device);
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switch (state)
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{
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/* --- the following bits of info are set as 64-bit signed integers --- */
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case CPUINFO_INT_SP: (void) info->i; /* no SP */ break;
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case CPUINFO_INT_PC:
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case CPUINFO_INT_REGISTER + TX0_PC: PC = info->i & cpustate->address_mask; break;
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case CPUINFO_INT_REGISTER + TX0_IR: IR = info->i & cpustate->ir_mask; /* weird idea */ break;
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case CPUINFO_INT_REGISTER + TX0_MBR: MBR = info->i & 0777777; break;
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case CPUINFO_INT_REGISTER + TX0_MAR: MAR = info->i & cpustate->address_mask; break;
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case CPUINFO_INT_REGISTER + TX0_AC: AC = info->i & 0777777; break;
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case CPUINFO_INT_REGISTER + TX0_LR: LR = info->i & 0777777; break;
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case CPUINFO_INT_REGISTER + TX0_XR: XR = info->i & 0037777; break;
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case CPUINFO_INT_REGISTER + TX0_PF: PF = info->i & 077; break;
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case CPUINFO_INT_REGISTER + TX0_TBR: cpustate->tbr = info->i & 0777777; break;
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case CPUINFO_INT_REGISTER + TX0_TAC: cpustate->tac = info->i & 0777777; break;
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case CPUINFO_INT_REGISTER + TX0_TSS00:
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case CPUINFO_INT_REGISTER + TX0_TSS01:
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case CPUINFO_INT_REGISTER + TX0_TSS02:
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case CPUINFO_INT_REGISTER + TX0_TSS03:
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case CPUINFO_INT_REGISTER + TX0_TSS04:
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case CPUINFO_INT_REGISTER + TX0_TSS05:
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case CPUINFO_INT_REGISTER + TX0_TSS06:
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case CPUINFO_INT_REGISTER + TX0_TSS07:
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case CPUINFO_INT_REGISTER + TX0_TSS10:
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case CPUINFO_INT_REGISTER + TX0_TSS11:
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case CPUINFO_INT_REGISTER + TX0_TSS12:
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case CPUINFO_INT_REGISTER + TX0_TSS13:
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case CPUINFO_INT_REGISTER + TX0_TSS14:
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case CPUINFO_INT_REGISTER + TX0_TSS15:
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case CPUINFO_INT_REGISTER + TX0_TSS16:
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case CPUINFO_INT_REGISTER + TX0_TSS17: cpustate->tss[state-(CPUINFO_INT_REGISTER + TX0_TSS00)] = info->i & 0777777; break;
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case CPUINFO_INT_REGISTER + TX0_CM_SEL: cpustate->cm_sel = info->i & 0177777; break;
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case CPUINFO_INT_REGISTER + TX0_LR_SEL: cpustate->lr_sel = info->i & 0177777; break;
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case CPUINFO_INT_REGISTER + TX0_GBL_CM_SEL: cpustate->gbl_cm_sel = info->i ? 1 : 0; break;
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case CPUINFO_INT_REGISTER + TX0_STOP_CYC0: cpustate->stop_cyc0 = info->i ? 1 : 0; break;
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case CPUINFO_INT_REGISTER + TX0_STOP_CYC1: cpustate->stop_cyc1 = info->i ? 1 : 0; break;
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case CPUINFO_INT_REGISTER + TX0_RUN: cpustate->run = info->i ? 1 : 0; break;
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case CPUINFO_INT_REGISTER + TX0_RIM: cpustate->rim = info->i ? 1 : 0; break;
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case CPUINFO_INT_REGISTER + TX0_CYCLE: if (LOG) logerror("tx0_set_reg to cycle counter ignored\n");/* no way!*/ break;
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case CPUINFO_INT_REGISTER + TX0_IOH: if (LOG) logerror("tx0_set_reg to ioh flip-flop ignored\n");/* no way!*/ break;
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case CPUINFO_INT_REGISTER + TX0_IOS: cpustate->ios = info->i ? 1 : 0; break;
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case CPUINFO_INT_REGISTER + TX0_RESET: pulse_reset(device); break;
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case CPUINFO_INT_REGISTER + TX0_IO_COMPLETE:cpustate->ios = 1; break;
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}
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}
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CPU_GET_INFO( tx0_64kw )
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{
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tx0_state *cpustate = ( device != NULL && device->token() != NULL ) ? get_safe_token(device) : NULL;
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switch (state)
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{
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/* --- the following bits of info are returned as 64-bit signed integers --- */
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case CPUINFO_INT_CONTEXT_SIZE: info->i = sizeof(tx0_state); break;
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case CPUINFO_INT_INPUT_LINES: info->i = 0; break;
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case CPUINFO_INT_DEFAULT_IRQ_VECTOR: info->i = 0; break;
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case CPUINFO_INT_ENDIANNESS: info->i = ENDIANNESS_BIG; /*don't care*/ break;
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case CPUINFO_INT_CLOCK_MULTIPLIER: info->i = 1; break;
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case CPUINFO_INT_CLOCK_DIVIDER: info->i = 1; break;
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case CPUINFO_INT_MIN_INSTRUCTION_BYTES: info->i = 4; break;
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case CPUINFO_INT_MAX_INSTRUCTION_BYTES: info->i = 4; break;
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case CPUINFO_INT_MIN_CYCLES: info->i = 1; break;
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case CPUINFO_INT_MAX_CYCLES: info->i = 3; break;
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case CPUINFO_INT_DATABUS_WIDTH + AS_PROGRAM: info->i = 32; break;
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case CPUINFO_INT_ADDRBUS_WIDTH + AS_PROGRAM: info->i = 16; break;
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case CPUINFO_INT_ADDRBUS_SHIFT + AS_PROGRAM: info->i = -2; break;
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case CPUINFO_INT_DATABUS_WIDTH + AS_DATA: info->i = 0; break;
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case CPUINFO_INT_ADDRBUS_WIDTH + AS_DATA: info->i = 0; break;
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case CPUINFO_INT_ADDRBUS_SHIFT + AS_DATA: info->i = 0; break;
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case CPUINFO_INT_DATABUS_WIDTH + AS_IO: info->i = 0; break;
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case CPUINFO_INT_ADDRBUS_WIDTH + AS_IO: info->i = 0; break;
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case CPUINFO_INT_ADDRBUS_SHIFT + AS_IO: info->i = 0; break;
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case CPUINFO_INT_SP: info->i = 0; /* no SP */ break;
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case CPUINFO_INT_PC: info->i = PC; break;
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case CPUINFO_INT_PREVIOUSPC: info->i = 0; /* TODO??? */ break;
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case CPUINFO_INT_REGISTER + TX0_PC: info->i = PC; break;
|
|
case CPUINFO_INT_REGISTER + TX0_IR: info->i = IR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_MBR: info->i = MBR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_MAR: info->i = MAR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_AC: info->i = AC; break;
|
|
case CPUINFO_INT_REGISTER + TX0_LR: info->i = LR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_XR: info->i = XR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_PF: info->i = PF; break;
|
|
case CPUINFO_INT_REGISTER + TX0_TBR: info->i = cpustate->tbr; break;
|
|
case CPUINFO_INT_REGISTER + TX0_TAC: info->i = cpustate->tac; break;
|
|
case CPUINFO_INT_REGISTER + TX0_TSS00:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS01:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS02:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS03:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS04:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS05:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS06:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS07:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS10:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS11:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS12:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS13:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS14:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS15:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS16:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS17: info->i = cpustate->tss[state-(CPUINFO_INT_REGISTER + TX0_TSS00)]; break;
|
|
case CPUINFO_INT_REGISTER + TX0_CM_SEL: info->i = cpustate->cm_sel; break;
|
|
case CPUINFO_INT_REGISTER + TX0_LR_SEL: info->i = cpustate->lr_sel; break;
|
|
case CPUINFO_INT_REGISTER + TX0_GBL_CM_SEL: info->i = cpustate->gbl_cm_sel; break;
|
|
case CPUINFO_INT_REGISTER + TX0_STOP_CYC0: info->i = cpustate->stop_cyc0; break;
|
|
case CPUINFO_INT_REGISTER + TX0_STOP_CYC1: info->i = cpustate->stop_cyc1; break;
|
|
case CPUINFO_INT_REGISTER + TX0_RUN: info->i = cpustate->run; break;
|
|
case CPUINFO_INT_REGISTER + TX0_RIM: info->i = cpustate->rim; break;
|
|
case CPUINFO_INT_REGISTER + TX0_CYCLE: info->i = cpustate->cycle; break;
|
|
case CPUINFO_INT_REGISTER + TX0_IOH: info->i = cpustate->ioh; break;
|
|
case CPUINFO_INT_REGISTER + TX0_IOS: info->i = cpustate->ios; break;
|
|
|
|
/* --- the following bits of info are returned as pointers to data or functions --- */
|
|
case CPUINFO_FCT_SET_INFO: info->setinfo = CPU_SET_INFO_NAME(tx0); break;
|
|
case CPUINFO_FCT_INIT: info->init = CPU_INIT_NAME(tx0_64kw); break;
|
|
case CPUINFO_FCT_RESET: info->reset = CPU_RESET_NAME(tx0); break;
|
|
case CPUINFO_FCT_EXECUTE: info->execute = CPU_EXECUTE_NAME(tx0_64kw); break;
|
|
case CPUINFO_FCT_BURN: info->burn = NULL; break;
|
|
case CPUINFO_FCT_DISASSEMBLE: info->disassemble = CPU_DISASSEMBLE_NAME(tx0_64kw); break;
|
|
case CPUINFO_PTR_INSTRUCTION_COUNTER: info->icount = &cpustate->icount; break;
|
|
|
|
/* --- the following bits of info are returned as NULL-terminated strings --- */
|
|
case CPUINFO_STR_NAME: strcpy(info->s, "TX-0"); break;
|
|
case CPUINFO_STR_SHORTNAME: strcpy(info->s, "tx0_64kw_cpu"); break;
|
|
case CPUINFO_STR_FAMILY: strcpy(info->s, "TX-0"); break;
|
|
case CPUINFO_STR_VERSION: strcpy(info->s, "1.0"); break;
|
|
case CPUINFO_STR_SOURCE_FILE: strcpy(info->s, __FILE__); break;
|
|
case CPUINFO_STR_CREDITS: strcpy(info->s, "Raphael Nabet"); break;
|
|
|
|
case CPUINFO_STR_FLAGS: strcpy(info->s, ""); break;
|
|
|
|
case CPUINFO_STR_REGISTER + TX0_PC: sprintf(info->s, "PC:0%06o", PC); break;
|
|
case CPUINFO_STR_REGISTER + TX0_IR: sprintf(info->s, "IR:0%02o", IR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_MBR: sprintf(info->s, "MBR:0%06o", MBR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_MAR: sprintf(info->s, "MAR:0%06o", MAR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_AC: sprintf(info->s, "AC:0%06o", AC); break;
|
|
case CPUINFO_STR_REGISTER + TX0_LR: sprintf(info->s, "LR:0%06o", LR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_XR: sprintf(info->s, "XR:0%05o", XR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_PF: sprintf(info->s, "PF:0%02o", PF); break;
|
|
case CPUINFO_STR_REGISTER + TX0_TBR: sprintf(info->s, "TBR:0%06o", cpustate->tbr); break;
|
|
case CPUINFO_STR_REGISTER + TX0_TAC: sprintf(info->s, "TAC:0%06o", cpustate->tac); break;
|
|
case CPUINFO_STR_REGISTER + TX0_TSS00:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS01:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS02:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS03:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS04:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS05:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS06:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS07:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS10:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS11:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS12:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS13:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS14:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS15:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS16:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS17: sprintf(info->s, "TSS%02o:0%06o", state-(CPUINFO_STR_REGISTER + TX0_TSS00), cpustate->tss[state-(CPUINFO_STR_REGISTER + TX0_TSS00)]); break;
|
|
case CPUINFO_STR_REGISTER + TX0_CM_SEL: sprintf(info->s, "CMSEL:0%06o", cpustate->cm_sel); break;
|
|
case CPUINFO_STR_REGISTER + TX0_LR_SEL: sprintf(info->s, "LRSEL:0%06o", cpustate->lr_sel); break;
|
|
case CPUINFO_STR_REGISTER + TX0_GBL_CM_SEL: sprintf(info->s, "GBLCMSEL:%X", cpustate->gbl_cm_sel); break;
|
|
case CPUINFO_STR_REGISTER + TX0_STOP_CYC0: sprintf(info->s, "STOPCYC0:%X", cpustate->stop_cyc0); break;
|
|
case CPUINFO_STR_REGISTER + TX0_STOP_CYC1: sprintf(info->s, "STOPCYC1:%X", cpustate->stop_cyc1); break;
|
|
case CPUINFO_STR_REGISTER + TX0_RUN: sprintf(info->s, "RUN:%X", cpustate->run); break;
|
|
case CPUINFO_STR_REGISTER + TX0_RIM: sprintf(info->s, "RIM:%X", cpustate->rim); break;
|
|
case CPUINFO_STR_REGISTER + TX0_CYCLE: sprintf(info->s, "CYCLE:%X", cpustate->cycle); break;
|
|
case CPUINFO_STR_REGISTER + TX0_IOH: sprintf(info->s, "IOH:%X", cpustate->ioh); break;
|
|
case CPUINFO_STR_REGISTER + TX0_IOS: sprintf(info->s, "IOS:%X", cpustate->ios); break;
|
|
case CPUINFO_IS_OCTAL: info->i = true; break;
|
|
}
|
|
}
|
|
|
|
CPU_GET_INFO( tx0_8kw )
|
|
{
|
|
tx0_state *cpustate = ( device != NULL && device->token() != NULL ) ? get_safe_token(device) : NULL;
|
|
|
|
switch (state)
|
|
{
|
|
/* --- the following bits of info are returned as 64-bit signed integers --- */
|
|
case CPUINFO_INT_CONTEXT_SIZE: info->i = sizeof(tx0_state); break;
|
|
case CPUINFO_INT_INPUT_LINES: info->i = 0; break;
|
|
case CPUINFO_INT_DEFAULT_IRQ_VECTOR: info->i = 0; break;
|
|
case CPUINFO_INT_ENDIANNESS: info->i = ENDIANNESS_BIG; /*don't care*/ break;
|
|
case CPUINFO_INT_CLOCK_MULTIPLIER: info->i = 1; break;
|
|
case CPUINFO_INT_CLOCK_DIVIDER: info->i = 1; break;
|
|
case CPUINFO_INT_MIN_INSTRUCTION_BYTES: info->i = 4; break;
|
|
case CPUINFO_INT_MAX_INSTRUCTION_BYTES: info->i = 4; break;
|
|
case CPUINFO_INT_MIN_CYCLES: info->i = 1; break;
|
|
case CPUINFO_INT_MAX_CYCLES: info->i = 3; break;
|
|
|
|
case CPUINFO_INT_DATABUS_WIDTH + AS_PROGRAM: info->i = 32; break;
|
|
case CPUINFO_INT_ADDRBUS_WIDTH + AS_PROGRAM: info->i = 13; break;
|
|
case CPUINFO_INT_ADDRBUS_SHIFT + AS_PROGRAM: info->i = -2; break;
|
|
case CPUINFO_INT_DATABUS_WIDTH + AS_DATA: info->i = 0; break;
|
|
case CPUINFO_INT_ADDRBUS_WIDTH + AS_DATA: info->i = 0; break;
|
|
case CPUINFO_INT_ADDRBUS_SHIFT + AS_DATA: info->i = 0; break;
|
|
case CPUINFO_INT_DATABUS_WIDTH + AS_IO: info->i = 0; break;
|
|
case CPUINFO_INT_ADDRBUS_WIDTH + AS_IO: info->i = 0; break;
|
|
case CPUINFO_INT_ADDRBUS_SHIFT + AS_IO: info->i = 0; break;
|
|
|
|
case CPUINFO_INT_SP: info->i = 0; /* no SP */ break;
|
|
case CPUINFO_INT_PC: info->i = PC; break;
|
|
case CPUINFO_INT_PREVIOUSPC: info->i = 0; /* TODO??? */ break;
|
|
|
|
case CPUINFO_INT_REGISTER + TX0_PC: info->i = PC; break;
|
|
case CPUINFO_INT_REGISTER + TX0_IR: info->i = IR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_MBR: info->i = MBR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_MAR: info->i = MAR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_AC: info->i = AC; break;
|
|
case CPUINFO_INT_REGISTER + TX0_LR: info->i = LR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_XR: info->i = XR; break;
|
|
case CPUINFO_INT_REGISTER + TX0_PF: info->i = PF; break;
|
|
case CPUINFO_INT_REGISTER + TX0_TBR: info->i = cpustate->tbr; break;
|
|
case CPUINFO_INT_REGISTER + TX0_TAC: info->i = cpustate->tac; break;
|
|
case CPUINFO_INT_REGISTER + TX0_TSS00:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS01:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS02:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS03:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS04:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS05:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS06:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS07:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS10:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS11:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS12:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS13:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS14:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS15:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS16:
|
|
case CPUINFO_INT_REGISTER + TX0_TSS17: info->i = cpustate->tss[state-(CPUINFO_INT_REGISTER + TX0_TSS00)]; break;
|
|
case CPUINFO_INT_REGISTER + TX0_CM_SEL: info->i = cpustate->cm_sel; break;
|
|
case CPUINFO_INT_REGISTER + TX0_LR_SEL: info->i = cpustate->lr_sel; break;
|
|
case CPUINFO_INT_REGISTER + TX0_GBL_CM_SEL: info->i = cpustate->gbl_cm_sel; break;
|
|
case CPUINFO_INT_REGISTER + TX0_STOP_CYC0: info->i = cpustate->stop_cyc0; break;
|
|
case CPUINFO_INT_REGISTER + TX0_STOP_CYC1: info->i = cpustate->stop_cyc1; break;
|
|
case CPUINFO_INT_REGISTER + TX0_RUN: info->i = cpustate->run; break;
|
|
case CPUINFO_INT_REGISTER + TX0_RIM: info->i = cpustate->rim; break;
|
|
case CPUINFO_INT_REGISTER + TX0_CYCLE: info->i = cpustate->cycle; break;
|
|
case CPUINFO_INT_REGISTER + TX0_IOH: info->i = cpustate->ioh; break;
|
|
case CPUINFO_INT_REGISTER + TX0_IOS: info->i = cpustate->ios; break;
|
|
|
|
/* --- the following bits of info are returned as pointers to data or functions --- */
|
|
case CPUINFO_FCT_SET_INFO: info->setinfo = CPU_SET_INFO_NAME(tx0); break;
|
|
case CPUINFO_FCT_INIT: info->init = CPU_INIT_NAME(tx0_8kw); break;
|
|
case CPUINFO_FCT_RESET: info->reset = CPU_RESET_NAME(tx0); break;
|
|
case CPUINFO_FCT_EXECUTE: info->execute = CPU_EXECUTE_NAME(tx0_8kw); break;
|
|
case CPUINFO_FCT_BURN: info->burn = NULL; break;
|
|
case CPUINFO_FCT_DISASSEMBLE: info->disassemble = CPU_DISASSEMBLE_NAME(tx0_8kw); break;
|
|
case CPUINFO_PTR_INSTRUCTION_COUNTER: info->icount = &cpustate->icount; break;
|
|
|
|
/* --- the following bits of info are returned as NULL-terminated strings --- */
|
|
case CPUINFO_STR_NAME: strcpy(info->s, "TX-0"); break;
|
|
case CPUINFO_STR_SHORTNAME: strcpy(info->s, "tx0_8kw_cpu"); break;
|
|
case CPUINFO_STR_FAMILY: strcpy(info->s, "TX-0"); break;
|
|
case CPUINFO_STR_VERSION: strcpy(info->s, "1.0"); break;
|
|
case CPUINFO_STR_SOURCE_FILE: strcpy(info->s, __FILE__); break;
|
|
case CPUINFO_STR_CREDITS: strcpy(info->s, "Raphael Nabet"); break;
|
|
|
|
case CPUINFO_STR_FLAGS: strcpy(info->s, ""); break;
|
|
|
|
case CPUINFO_STR_REGISTER + TX0_PC: sprintf(info->s, "PC:0%06o", PC); break;
|
|
case CPUINFO_STR_REGISTER + TX0_IR: sprintf(info->s, "IR:0%02o", IR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_MBR: sprintf(info->s, "MBR:0%06o", MBR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_MAR: sprintf(info->s, "MAR:0%06o", MAR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_AC: sprintf(info->s, "AC:0%06o", AC); break;
|
|
case CPUINFO_STR_REGISTER + TX0_LR: sprintf(info->s, "LR:0%06o", LR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_XR: sprintf(info->s, "XR:0%05o", XR); break;
|
|
case CPUINFO_STR_REGISTER + TX0_PF: sprintf(info->s, "PF:0%02o", PF); break;
|
|
case CPUINFO_STR_REGISTER + TX0_TBR: sprintf(info->s, "TBR:0%06o", cpustate->tbr); break;
|
|
case CPUINFO_STR_REGISTER + TX0_TAC: sprintf(info->s, "TAC:0%06o", cpustate->tac); break;
|
|
case CPUINFO_STR_REGISTER + TX0_TSS00:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS01:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS02:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS03:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS04:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS05:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS06:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS07:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS10:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS11:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS12:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS13:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS14:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS15:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS16:
|
|
case CPUINFO_STR_REGISTER + TX0_TSS17: sprintf(info->s, "TSS%02o:0%06o", state-(CPUINFO_STR_REGISTER + TX0_TSS00), cpustate->tss[state-(CPUINFO_STR_REGISTER + TX0_TSS00)]); break;
|
|
case CPUINFO_STR_REGISTER + TX0_CM_SEL: sprintf(info->s, "CMSEL:0%06o", cpustate->cm_sel); break;
|
|
case CPUINFO_STR_REGISTER + TX0_LR_SEL: sprintf(info->s, "LRSEL:0%06o", cpustate->lr_sel); break;
|
|
case CPUINFO_STR_REGISTER + TX0_GBL_CM_SEL: sprintf(info->s, "GBLCMSEL:%X", cpustate->gbl_cm_sel); break;
|
|
case CPUINFO_STR_REGISTER + TX0_STOP_CYC0: sprintf(info->s, "STOPCYC0:%X", cpustate->stop_cyc0); break;
|
|
case CPUINFO_STR_REGISTER + TX0_STOP_CYC1: sprintf(info->s, "STOPCYC1:%X", cpustate->stop_cyc1); break;
|
|
case CPUINFO_STR_REGISTER + TX0_RUN: sprintf(info->s, "RUN:%X", cpustate->run); break;
|
|
case CPUINFO_STR_REGISTER + TX0_RIM: sprintf(info->s, "RIM:%X", cpustate->rim); break;
|
|
case CPUINFO_STR_REGISTER + TX0_CYCLE: sprintf(info->s, "CYCLE:%X", cpustate->cycle); break;
|
|
case CPUINFO_STR_REGISTER + TX0_IOH: sprintf(info->s, "IOH:%X", cpustate->ioh); break;
|
|
case CPUINFO_STR_REGISTER + TX0_IOS: sprintf(info->s, "IOS:%X", cpustate->ios); break;
|
|
case CPUINFO_IS_OCTAL: info->i = true; break;
|
|
}
|
|
}
|
|
|
|
|
|
/* execute one instruction */
|
|
static void execute_instruction_64kw(device_t *device)
|
|
{
|
|
tx0_state *cpustate = get_safe_token(device);
|
|
|
|
if (! cpustate->cycle)
|
|
{
|
|
cpustate->cycle = 1; /* most frequent case */
|
|
switch (IR)
|
|
{
|
|
case 0: /* STOre */
|
|
case 1: /* ADD */
|
|
break;
|
|
|
|
case 2: /* TRansfer on Negative */
|
|
if (AC & 0400000)
|
|
{
|
|
PC = MAR & ADDRESS_MASK_64KW;
|
|
cpustate->cycle = 0; /* instruction only takes one cycle if branch
|
|
is taken */
|
|
}
|
|
break;
|
|
|
|
case 3: /* OPeRate */
|
|
if (MAR & 0100000)
|
|
/* (0.8) CLL = Clear the left nine digital positions of the AC */
|
|
AC &= 0000777;
|
|
|
|
if (MAR & 0040000)
|
|
/* (0.8) CLR = Clear the right nine digital positions of the AC */
|
|
AC &= 0777000;
|
|
|
|
if (((MAR & 0030000) >> 12) == 1)
|
|
/* (0.8) IOS In-Out Stop = Stop machine so that an In-Out command
|
|
(specified by digits 6 7 8 of MAR) may be executed */
|
|
cpustate->ioh = 1;
|
|
|
|
if (((MAR & 0007000) >> 9) != 0)
|
|
{
|
|
/* ((MAR & 0007000) >> 9) is device ID */
|
|
/* 7: */
|
|
/* (0.8) P7H = Punch holes 1-6 in flexo tape specified by AC
|
|
digital positions 2, 5, 8, 11, 14, and 17. Also punches a 7th
|
|
hole on tape. */
|
|
/* 6: */
|
|
/* (0.8) P6H = Same as P7H but no seventh hole */
|
|
/* 4: */
|
|
/* (0.8) PNT = Print one flexowriter character specified by AC
|
|
digits 2, 5, 8, 11, 14, and 17. */
|
|
/* 1: */
|
|
/* (0.8) R1C = Read one line of flexo tape so that tape positions
|
|
1, 2, 3, 4, 5, and 6 will be put in the AC digital positions 0,
|
|
3, 6, 9, 12 and 15. */
|
|
/* 3: */
|
|
/* (0.8) R3C = Read one line of flexo tape into AC digits 0, 3, 6,
|
|
9, 12 and 15. Then cycle the AC one digital position; read the
|
|
next line on tape into AC digits 0, 3, 6, 9, 12 and 15, cycle
|
|
the AC right one digital position and read the third and last
|
|
line into AC digits 0, 3, 6, 9, 12 and 15. (This command is
|
|
equal to a triple CYR-R1C.) */
|
|
/* 2: */
|
|
/* (0.8) DIS = Intensify a point on the scope with x and y
|
|
coordinates where x is specified by AC digits 0-8 with digit 0
|
|
being used as the sign and y is specified by AC digits 9-17
|
|
with digit 9 being used as the sign for y. The complement
|
|
system is in effect when the signs are negative. */
|
|
/* (5 is undefined) */
|
|
int index = (MAR & 0007000) >> 9;
|
|
|
|
if (cpustate->iface->io_handlers[index])
|
|
(*cpustate->iface->io_handlers[index])(device);
|
|
cpustate->ioh = 1;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
cpustate->cycle = 0; /* always true */
|
|
switch (IR)
|
|
{
|
|
case 0: /* STOre */
|
|
tx0_write(cpustate, MAR, (MBR = AC));
|
|
break;
|
|
|
|
case 1: /* ADD */
|
|
MBR = tx0_read(cpustate, MAR);
|
|
|
|
AC = AC + MBR;
|
|
AC = (AC + (AC >> 18)) & 0777777; /* propagate carry around */
|
|
|
|
if (AC == 0777777) /* check for -0 */
|
|
AC = 0;
|
|
break;
|
|
|
|
case 2: /* TRansfer on Negative */
|
|
break;
|
|
|
|
case 3: /* OPeRate */
|
|
if ((MAR & 0000104) == 0000100)
|
|
/* (1.1) PEN = Read the light pen flip-flops 1 and 2 into AC(0) and
|
|
AC(1). */
|
|
/*...*/{ }
|
|
|
|
if ((MAR & 0000104) == 0000004)
|
|
/* (1.1) TAC = Insert a one in each digital position of the AC
|
|
wherever there is a one in the corresponding digital position
|
|
of the TAC. */
|
|
/*...*/ { }
|
|
|
|
if (MAR & 0000040)
|
|
/* (1.2) COM = Complement every digit in the accumulator */
|
|
AC ^= 0777777;
|
|
|
|
if ((MAR & 0000003) == 1)
|
|
/* (1.2) AMB = Store the contents of the AC in the MBR. */
|
|
MBR = AC;
|
|
|
|
if ((MAR & 0000003) == 3)
|
|
/* (1.2) TBR = Store the contents of the TBR in the MBR. */
|
|
/*...*/ { }
|
|
|
|
if ((MAR & 0000003) == 2)
|
|
/* (1.3) LMB = Store the contents of the LR in the MBR. */
|
|
MBR = LR;
|
|
break;
|
|
|
|
if (((MAR & 0000600) >> 7) == 1)
|
|
/* (1.3) MLR = Store the contents of the MBR (memory buffer
|
|
register) in the live reg. */
|
|
LR = MBR;
|
|
|
|
if (((MAR & 0000600) >> 7) == 2)
|
|
/* (1.4) SHR = Shift the AC right one place, i.e. multiply the AC
|
|
by 2^-1 */
|
|
AC >>= 1;
|
|
|
|
if (((MAR & 0000600) >> 7) == 3)
|
|
/* (1.4) CYR = Cycle the AC right one digital position (AC(17) will
|
|
become AC(0)) */
|
|
AC = (AC >> 1) | ((AC & 1) << 17);
|
|
|
|
if (MAR & 0000020)
|
|
/* (1.4) PAD = Partial add AC to MBR, that is, for every digital
|
|
position of the MBR that contains a one, complement the digit
|
|
in the corresponding digital position of the AC. This is also
|
|
called a half add. */
|
|
AC ^= MBR;
|
|
|
|
if (MAR & 0000010)
|
|
{ /* (1.7) CRY = Partial add the 18 digits of the AC to the
|
|
corresponding 18 digits of the carry.
|
|
|
|
To determine what the 18 digits of the carry are, use the
|
|
following rule:
|
|
|
|
"Grouping the AC and MBR digits into pairs and proceeding from
|
|
right to left, assign the carry digit of the next pair to a one
|
|
if in the present pair MBR = 1 and AC = 0 or if in the present
|
|
pair AC = 1 and carry 1.
|
|
|
|
(Note: the 0th digit pair determines the 17th pair's carry
|
|
digit)" */
|
|
AC ^= MBR;
|
|
|
|
AC = AC + MBR;
|
|
AC = (AC + (AC >> 18)) & 0777777; /* propagate carry around */
|
|
|
|
if (AC == 0777777) /* check for -0 */
|
|
AC = 0;
|
|
}
|
|
|
|
if (((MAR & 0030000) >> 12) == 3)
|
|
/* (1.8) Hlt = Halt the computer */
|
|
cpustate->run = 0;
|
|
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void indexed_address_eval(tx0_state *cpustate)
|
|
{
|
|
MAR = MAR + XR;
|
|
MAR = (MAR + (MAR >> 14)) & 0037777; /* propagate carry around */
|
|
//if (MAR == 0037777) /* check for -0 */
|
|
// MAR = 0;
|
|
if (MAR & 0020000) /* fix negative (right???) */
|
|
MAR = (MAR + 1) & 0017777;
|
|
}
|
|
|
|
/* execute one instruction */
|
|
static void execute_instruction_8kw(device_t *device)
|
|
{
|
|
tx0_state *cpustate = get_safe_token(device);
|
|
|
|
if (! cpustate->cycle)
|
|
{
|
|
cpustate->cycle = 1; /* most frequent case */
|
|
switch (IR)
|
|
{
|
|
case 0: /* STOre */
|
|
case 1: /* STore indeXed */
|
|
case 2: /* Store indeX in Address */
|
|
case 3: /* ADd One */
|
|
case 4: /* Store LR */
|
|
case 5: /* Store Lr indeXed */
|
|
case 6: /* STore Zero */
|
|
case 8: /* ADD */
|
|
case 9: /* ADd indeXed */
|
|
case 10: /* LoaD indeX */
|
|
case 11: /* AUgment indeX */
|
|
case 12: /* Load LR */
|
|
case 13: /* Load Lr indeXed */
|
|
case 14: /* LoaD Ac */
|
|
case 15: /* Load Ac indeXed */
|
|
break;
|
|
|
|
case 16: /* TRansfer on Negative */
|
|
if (AC & 0400000)
|
|
{
|
|
PC = MAR & 0017777;
|
|
cpustate->cycle = 0; /* instruction only takes one cycle if branch
|
|
is taken */
|
|
}
|
|
break;
|
|
|
|
case 17: /* Transfer on ZEro */
|
|
if ((AC == 0000000) || (AC == 0777777))
|
|
{
|
|
PC = MAR & 0017777;
|
|
cpustate->cycle = 0; /* instruction only takes one cycle if branch
|
|
is taken */
|
|
}
|
|
break;
|
|
|
|
case 18: /* Transfer and Set indeX */
|
|
XR = PC;
|
|
PC = MAR & 0017777;
|
|
cpustate->cycle = 0; /* instruction only takes one cycle if branch
|
|
is taken */
|
|
break;
|
|
|
|
case 19: /* Transfer and IndeX */
|
|
if ((XR != 0000000) && (XR != 0037777))
|
|
{
|
|
if (XR & 0020000)
|
|
XR ++;
|
|
else
|
|
XR--;
|
|
PC = MAR & 0017777;
|
|
cpustate->cycle = 0; /* instruction only takes one cycle if branch
|
|
is taken */
|
|
}
|
|
break;
|
|
|
|
case 21: /* TRansfer indeXed */
|
|
indexed_address_eval(cpustate);
|
|
case 20: /* TRAnsfer */
|
|
PC = MAR & 0017777;
|
|
cpustate->cycle = 0; /* instruction only takes one cycle if branch
|
|
is taken */
|
|
break;
|
|
|
|
case 22: /* Transfer on external LeVel */
|
|
/*if (...)
|
|
{
|
|
PC = MAR & 0017777;
|
|
cpustate->cycle = 0;*/ /* instruction only takes one cycle if branch
|
|
is taken */
|
|
/*}*/
|
|
break;
|
|
|
|
case 24: /* OPeRate */
|
|
case 25:
|
|
case 26:
|
|
case 27:
|
|
case 28:
|
|
case 29:
|
|
case 30:
|
|
case 31:
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 004000))
|
|
{ /* Select class instruction */
|
|
if (IR & 004)
|
|
/* (0.8???) CLA = CLear Ac */
|
|
AC = 0;
|
|
|
|
/* (IOS???) SEL = SELect */
|
|
if (cpustate->iface->sel_handler)
|
|
(*cpustate->iface->sel_handler)(device);
|
|
}
|
|
else
|
|
{ /* Normal operate class instruction */
|
|
if (((IR & 001) == 01) && ((MAR & 017000) == 011000))
|
|
/* (0.6) CLL = CLear Left 9 bits of ac */
|
|
AC &= 0000777;
|
|
|
|
if (((IR & 001) == 01) && ((MAR & 017000) == 012000))
|
|
/* (0.6) CLR = CLear Right 9 bits of ac */
|
|
AC &= 0777000;
|
|
|
|
if (IR & 002)
|
|
/* (0.7) AMB = transfer Ac to MBr */
|
|
MBR = AC;
|
|
|
|
if (IR & 004)
|
|
/* (0.8) CLA = CLear Ac */
|
|
AC = 0;
|
|
|
|
if (((IR & 001) == 01) && ((MAR & 010000) == 000000))
|
|
{ /* (IOS) In-Out group commands */
|
|
/* ((MAR & 0007000) >> 9) is device ID */
|
|
/* 0: */
|
|
/* (***) CPY = CoPY synchronizes transmission of information
|
|
between in-out equipment and computer. */
|
|
/* 1: */
|
|
/* (IOS) R1L = Read 1 Line of tape from PETR into AC bits 0, 3,
|
|
6, 9, 12, 15, with CYR before read (inclusive or) */
|
|
/* 3: */
|
|
/* (IOS) R3L = Read 3 Lines of tape from PETR into AC bits 0,
|
|
3, 6, 9, 12, 15, with CYR before each read (inclusive or) */
|
|
/* 2: */
|
|
/* (IOS) DIS = DISplay a point on scope (AC bits 0-8 specify x
|
|
coordinate, AC bits 9-17 specify y coordinate). The
|
|
coordinate (0, 0) is usually at the lower left hand corner
|
|
of the scope. A console switch is available to relocate
|
|
(0,0) to the center. */
|
|
/* 6: */
|
|
/* (IOS) P6H = Punch one 6-bit line of flexo tape (without 7th
|
|
hole) from ac bits 2, 5, 8, 11, 14, 17. Note: lines
|
|
without 7th hole are ignored by PETR. */
|
|
/* 7: */
|
|
/* (IOS) P7H = same as P6H, but with 7th hole */
|
|
/* 4: */
|
|
/* (IOS) PRT = Print one six bit flexo character from AC bits
|
|
2, 5, 8, 11, 14, 17. */
|
|
/* (5 is undefined) */
|
|
int index = (MAR & 0007000) >> 9;
|
|
|
|
if (cpustate->iface->io_handlers[index])
|
|
(*cpustate->iface->io_handlers[index])(device);
|
|
cpustate->ioh = 1;
|
|
}
|
|
|
|
if (((IR & 001) == 00) && ((MAR & 010000) == 010000))
|
|
{ /* (IOS) EX0 through EX7 = operate user's EXternal equipment. */
|
|
switch ((MAR & 0007000) >> 9)
|
|
{
|
|
/* ... */
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (((IR != 2) && (IR != 3)) || (cpustate->cycle == 2))
|
|
cpustate->cycle = 0;
|
|
else
|
|
cpustate->cycle = 2; /* SXA and ADO have an extra cycle 2 */
|
|
switch (IR)
|
|
{
|
|
case 1: /* STore indeXed */
|
|
indexed_address_eval(cpustate);
|
|
case 0: /* STOre */
|
|
tx0_write(cpustate, MAR, (MBR = AC));
|
|
break;
|
|
|
|
case 2: /* Store indeX in Address */
|
|
if (cpustate->cycle)
|
|
{ /* cycle 1 */
|
|
MBR = tx0_read(cpustate, MAR);
|
|
MBR = (MBR & 0760000) | (XR & 0017777);
|
|
}
|
|
else
|
|
{ /* cycle 2 */
|
|
tx0_write(cpustate, MAR, MBR);
|
|
}
|
|
break;
|
|
|
|
case 3: /* ADd One */
|
|
if (cpustate->cycle)
|
|
{ /* cycle 1 */
|
|
AC = tx0_read(cpustate, MAR) + 1;
|
|
|
|
#if 0
|
|
AC = (AC + (AC >> 18)) & 0777777; /* propagate carry around */
|
|
if (AC == 0777777) /* check for -0 (right???) */
|
|
AC = 0;
|
|
#else
|
|
if (AC >= 0777777)
|
|
AC = (AC + 1) & 0777777;
|
|
#endif
|
|
}
|
|
else
|
|
{ /* cycle 2 */
|
|
tx0_write(cpustate, MAR, (MBR = AC));
|
|
}
|
|
break;
|
|
|
|
case 5: /* Store Lr indeXed */
|
|
indexed_address_eval(cpustate);
|
|
case 4: /* Store LR */
|
|
tx0_write(cpustate, MAR, (MBR = LR));
|
|
break;
|
|
|
|
case 6: /* STore Zero */
|
|
tx0_write(cpustate, MAR, (MBR = 0));
|
|
break;
|
|
|
|
case 9: /* ADd indeXed */
|
|
indexed_address_eval(cpustate);
|
|
case 8: /* ADD */
|
|
MBR = tx0_read(cpustate, MAR);
|
|
|
|
AC = AC + MBR;
|
|
AC = (AC + (AC >> 18)) & 0777777; /* propagate carry around */
|
|
|
|
if (AC == 0777777) /* check for -0 */
|
|
AC = 0;
|
|
break;
|
|
|
|
case 10: /* LoaD indeX */
|
|
MBR = tx0_read(cpustate, MAR);
|
|
XR = (MBR & 0017777) | ((MBR >> 4) & 0020000);
|
|
break;
|
|
|
|
case 11: /* AUgment indeX */
|
|
MBR = tx0_read(cpustate, MAR);
|
|
|
|
XR = XR + ((MBR & 0017777) | ((MBR >> 4) & 0020000));
|
|
XR = (XR + (XR >> 14)) & 0037777; /* propagate carry around */
|
|
|
|
//if (XR == 0037777) /* check for -0 */
|
|
// XR = 0;
|
|
break;
|
|
|
|
case 13: /* Load Lr indeXed */
|
|
indexed_address_eval(cpustate);
|
|
case 12: /* Load LR */
|
|
LR = MBR = tx0_read(cpustate, MAR);
|
|
break;
|
|
|
|
case 15: /* Load Ac indeXed */
|
|
indexed_address_eval(cpustate);
|
|
case 14: /* LoaD Ac */
|
|
AC = MBR = tx0_read(cpustate, MAR);
|
|
break;
|
|
|
|
case 16: /* TRansfer on Negative */
|
|
case 17: /* Transfer on ZEro */
|
|
case 18: /* Transfer and Set indeX */
|
|
case 19: /* Transfer and IndeX */
|
|
case 20: /* TRAnsfer */
|
|
case 21: /* TRansfer indeXed */
|
|
case 22: /* Transfer on external LeVel */
|
|
break;
|
|
|
|
case 24: /* OPeRate */
|
|
case 25:
|
|
case 26:
|
|
case 27:
|
|
case 28:
|
|
case 29:
|
|
case 30:
|
|
case 31:
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 004000))
|
|
{ /* Select class instruction */
|
|
}
|
|
else
|
|
{ /* Normal operate class instruction */
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 003000))
|
|
{ /* (1.1) PEN = set ac bit 0 from light PEN ff, and ac bit 1 from
|
|
light gun ff. (ffs contain one if pen or gun saw displayed
|
|
point.) Then clear both light pen and light gun ffs */
|
|
/*AC = (AC & 0177777) |?...;*/
|
|
/*... = 0;*/
|
|
}
|
|
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 001000))
|
|
/* (1.1) TAC = transfer TAC into ac (inclusive or) */
|
|
AC |= cpustate->tac;
|
|
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 002000))
|
|
/* (1.2) TBR = transfer TBR into mbr (inclusive or) */
|
|
MBR |= cpustate->tbr;
|
|
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 006000))
|
|
/* (1.2) RPF = Read Program Flag register into mbr (inclusive or) */
|
|
MBR |= PF << 8;
|
|
|
|
if (MAR & 0000040)
|
|
/* (1.2) COM = COMplement ac */
|
|
AC ^= 0777777;
|
|
|
|
if ((! (MAR & 0000400)) && (MAR & 0000100))
|
|
{ /* (1.2) XMB = Transfer XR contents to MBR */
|
|
MBR = XR;
|
|
if (XR & 0020000)
|
|
MBR |= 0740000;
|
|
}
|
|
|
|
if (MAR & 0000004)
|
|
{
|
|
switch (MAR & 0000003)
|
|
{
|
|
case 0000003: /* (1.2) And LR and MBR */
|
|
MBR &= LR;
|
|
break;
|
|
|
|
case 0000001: /* (1.3) Or LR into MBR */
|
|
MBR |= LR;
|
|
break;
|
|
|
|
default:
|
|
if (LOG)
|
|
logerror("unrecognized instruction");
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (((! (MAR & 0000400)) && (MAR & 0000200)) && ((! (MAR & 0000004)) && (MAR & 0000002)))
|
|
{ /* LMB and MBL used simultaneously interchange LR and MBR */
|
|
int tmp = MBR;
|
|
MBR = LR;
|
|
LR = tmp;
|
|
}
|
|
else if ((! (MAR & 0000400)) && (MAR & 0000200))
|
|
/* (1.4) MBL = Transfer MBR contents to LR */
|
|
LR = MBR;
|
|
else if ((! (MAR & 0000004)) && (MAR & 0000002))
|
|
/* (1.4) LMB = Store the contents of the LR in the MBR. */
|
|
MBR = LR;
|
|
|
|
if (MAR & 0000020)
|
|
/* (1.5) PAD = Partial ADd mbr to ac */
|
|
AC ^= MBR;
|
|
|
|
if (MAR & 0000400)
|
|
{
|
|
switch (MAR & 0000300)
|
|
{
|
|
case 0000000: /* (1.6) CYR = CYcle ac contents Right one binary
|
|
position (AC(17) -> AC(0)) */
|
|
AC = (AC >> 1) | ((AC & 1) << 17);
|
|
break;
|
|
|
|
case 0000200: /* (1.6) CYcle ac contents Right one binary
|
|
position (AC(0) unchanged) */
|
|
AC = (AC >> 1) | (AC & 0400000);
|
|
break;
|
|
|
|
default:
|
|
if (LOG)
|
|
logerror("unrecognized instruction");
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (((IR & 001) == 00) && ((MAR & 017000) == 007000))
|
|
/* (1.6) SPF = Set Program Flag register from mbr */
|
|
PF = (MBR >> 8) & 077;
|
|
|
|
if (MAR & 0000010)
|
|
{ /* (1.7?) CRY = Partial ADd the 18 digits of the AC to the
|
|
corresponding 18 digits of the carry. */
|
|
AC ^= MBR;
|
|
|
|
AC = AC + MBR;
|
|
AC = (AC + (AC >> 18)) & 0777777; /* propagate carry around */
|
|
|
|
if (AC == 0777777) /* check for -0 */
|
|
AC = 0;
|
|
}
|
|
|
|
if ((! (MAR & 0000004)) && (MAR & 0000001))
|
|
/* (1.8) MBX = Transfer MBR contents to XR */
|
|
XR = (MBR & 0017777) | ((MBR >> 4) & 0020000);
|
|
|
|
if (((IR & 001) == 01) && ((MAR & 017000) == 010000))
|
|
/* (1.8) HLT = HaLT the computer and sound chime */
|
|
cpustate->run = 0;
|
|
}
|
|
break;
|
|
|
|
default: /* Illegal */
|
|
/* ... */
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
Simulate a pulse on reset line:
|
|
reset most registers and flip-flops, and initialize a few emulator state
|
|
variables.
|
|
*/
|
|
static void pulse_reset(device_t *device)
|
|
{
|
|
tx0_state *cpustate = get_safe_token(device);
|
|
|
|
/* processor registers */
|
|
PC = 0; /* ??? */
|
|
IR = 0; /* ??? */
|
|
/*MBR = 0;*/ /* ??? */
|
|
/*MAR = 0;*/ /* ??? */
|
|
/*AC = 0;*/ /* ??? */
|
|
/*LR = 0;*/ /* ??? */
|
|
|
|
/* processor state flip-flops */
|
|
cpustate->run = 0; /* ??? */
|
|
cpustate->rim = 0; /* ??? */
|
|
cpustate->ioh = 0; /* ??? */
|
|
cpustate->ios = 0; /* ??? */
|
|
|
|
cpustate->rim_step = 0;
|
|
|
|
/* now, we kindly ask IO devices to reset, too */
|
|
if (cpustate->iface->io_reset_callback)
|
|
(*cpustate->iface->io_reset_callback)(device);
|
|
}
|
|
|
|
DEFINE_LEGACY_CPU_DEVICE(TX0_64KW, tx0_64kw);
|
|
DEFINE_LEGACY_CPU_DEVICE(TX0_8KW, tx0_8kw);
|