Miroirs/mame
1
0
Fork 0
mirror of https://github.com/mamedev/mame.git synced 2024-11-16 07:48:32 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions 3

mc6843: Clear STRB bits when read (mostly reverts 05803c6130)

Browse source
This commit is contained in:
AJR 2022-12-13 10:42:59 -05:00
parent 05803c6130
commit 14c847d681
1 changed files with 21 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

35
src/devices/machine/mc6843.cpp
View file

@ -126,6 +126,10 @@ void mc6843_device::dor_w(u8 data)
m_dor = data;
m_dor_loaded = true;
logerror("dor_w %02x\n", m_dor);
m_strb &= ~SB_DTERR;
if(m_strb == 0)
m_isr &= 0x7;
}
u8 mc6843_device::ctar_r()
@ -238,18 +242,22 @@ void mc6843_device::sur_w(u8 data)
u8 mc6843_device::strb_r()
{
u8 strb = m_strb;
if(!machine().side_effects_disabled()) {
logerror("strb_r %02x -%s%s%s%s%s%s%s%s\n", m_strb,
m_strb & SB_HERR ? " herr" : "",
m_strb & SB_WERR ? " werr" : "",
m_strb & SB_FI ? " fi" : "",
m_strb & SB_SERR ? " serr" : "",
m_strb & SB_SAERR ? " saerr" : "",
m_strb & SB_DMERR ? " dmerr" : "",
m_strb & SB_CRC ? " crc" : "",
m_strb & SB_DTERR ? " dterr" : "");
logerror("strb_r %02x -%s%s%s%s%s%s%s%s\n", strb,
strb & SB_HERR ? " herr" : "",
strb & SB_WERR ? " werr" : "",
strb & SB_FI ? " fi" : "",
strb & SB_SERR ? " serr" : "",
strb & SB_SAERR ? " saerr" : "",
strb & SB_DMERR ? " dmerr" : "",
strb & SB_CRC ? " crc" : "",
strb & SB_DTERR ? " dterr" : "");
m_strb &= ~(SB_HERR|SB_WERR|SB_SERR|SB_SAERR|SB_DMERR|SB_CRC|SB_DTERR);
if(m_strb == 0)
m_isr &= 0x7;
}
return m_strb;
return strb;
}
void mc6843_device::sar_w(u8 data)
@ -308,10 +316,6 @@ TIMER_CALLBACK_MEMBER(mc6843_device::update_tick)
void mc6843_device::command_start()
{
// clear errors
m_strb = 0;
m_isr &= 0x7;
assert(m_state == S_IDLE);
switch(m_cmr & 0xf) {
@ -346,6 +350,9 @@ void mc6843_device::command_start()
case C_SSR: case C_RCR: case C_SSW: case C_SWD: case C_MSR: case C_MSW:
m_stra |= SA_BUSY;
m_stra &= ~(SA_DDM|SA_TNEQ);
m_strb &= ~SB_DMERR;
if(m_strb == 0)
m_isr &= 0x7;
m_state = S_SRW_WAIT_READY;
break;