57 lines
1.8 KiB
Plaintext
57 lines
1.8 KiB
Plaintext
%include include\gigatron.i
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%include include\macros.i
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ii EQU 0x30
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jj EQU 0x31
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kk EQU 0x32
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ll EQU 0x33
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xx EQU 0x34
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yy EQU 0x35
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; clears the viewable screen
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clearScreen LDWI SYS_Draw4_30 ; setup 4 pixel SYS routine
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STW giga_sysFn
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LDWI 0x0000 ; 4 pixels of colour
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STW giga_sysArg0
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STW giga_sysArg2
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LDI giga_yres / 2 ; counters
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ST jj
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LDI giga_xres / 4
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ST ii
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LDWI 0x0800 ; top line
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STW xx
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LDWI 0x7F00 ; bottom line
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STW kk
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clearS_loop LDW xx
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STW giga_sysArg4 ; top line
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SYS 30
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LDW kk
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STW giga_sysArg4 ; bottom line
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SYS 30
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LD xx ; 4 horizontal pixels
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ADDI 0x04
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ST xx
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LD kk ; 4 horizontal pixels
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ADDI 0x04
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ST kk
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LoopCounterTo1 ii clearS_loop
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INC yy ; next top line
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LD ll ; next bottom line
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SUBI 0x01
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ST ll
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LDI 0x00 ; reset xx, kk and ii
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ST xx
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ST kk
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LDI giga_xres / 4
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ST ii
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LoopCounterTo1 jj clearS_loop
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loop BRA loop |