Sprinter/mame
2
0
Fork 0
mirror of https://github.com/holub/mame synced 2025-04-22 00:11:58 +03:00
Code Issues Actions Packages Projects Releases Wiki Activity

m68000: Fix the vpa wait state, make using irq 7/NMI a little more transparent

Browse Source
This commit is contained in:
Olivier Galibert 2023-02-22 17:06:34 +01:00
parent a9ed015bdb
commit b4bc3be8d1
2 changed files with 17 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
src/devices/cpu/m68000/m68000.cpp
View File

@ -53,12 +53,14 @@ void m68000_device::do_post_run()
u64 m68000_device::vpa_sync(offs_t, u64 current_time)
{
if(m_last_vpa_time >= current_time)
return m_last_vpa_time;
u64 mod = current_time % 10;
if(mod < 7)
current_time = current_time - mod + 10;
m_last_vpa_time = current_time - mod + 10;
else
current_time = current_time - mod + 20;
return current_time;
m_last_vpa_time = current_time - mod + 20;
return m_last_vpa_time;
}
u32 m68000_device::vpa_after(offs_t)
@ -223,6 +225,8 @@ void m68000_device::device_start()
save_item(NAME(m_t));
save_item(NAME(m_post_run));
save_item(NAME(m_post_run_cycles));
save_item(NAME(m_nmi_uses_generic));
save_item(NAME(m_last_vpa_time));
memset(m_da, 0, sizeof(m_da));
m_ipc = 0;
@ -257,6 +261,8 @@ void m68000_device::device_start()
m_count_before_instruction_step = 0;
m_bcount = 0;
m_t = 0;
m_nmi_uses_generic = false;
m_last_vpa_time = 0;
state_add(STATE_GENPCBASE, "PC", m_ipc).callimport();
state_add(STATE_GENPC, "rPC", m_pc);
@ -338,8 +344,12 @@ void m68000_device::update_user_super()
void m68000_device::execute_set_input(int inputnum, int state)
{
if(inputnum == INPUT_LINE_NMI)
if(inputnum == INPUT_LINE_NMI) {
inputnum = 7;
m_nmi_uses_generic = true;
} else if(inputnum == 7)
m_nmi_uses_generic = false;
if(inputnum > (m_interrupt_mixer ? 7 : 3))
return;
@ -420,7 +430,7 @@ void m68000_device::start_interrupt_vector_lookup()
int level = m_next_state >> 24;
if(m_interrupt_mixer)
standard_irq_callback(level);
standard_irq_callback(level == 7 && m_nmi_uses_generic ? INPUT_LINE_NMI : level);
else {
for(int i=0; i<3; i++)
if(level & (1<<i))

2
src/devices/cpu/m68000/m68000.h
View File

@ -165,6 +165,8 @@ protected:
u32 m_nmi_pending;
u32 m_int_level;
u32 m_int_next_state;
bool m_nmi_uses_generic;
u64 m_last_vpa_time;
// Current instruction state and substate
u16 m_inst_state;