6502/EightBit
1
0
Fork 0
mirror of https://github.com/MoleskiCoder/EightBit.git synced 2025-01-01 11:29:17 +00:00
Code Issues Projects Releases Wiki Activity

Z80: Better interrupt timing response.

Browse Source
This commit is contained in:
Adrian Conlon 2020-12-27 15:45:14 +00:00
parent 28ae32b8a2
commit 778aacaef6
1 changed files with 2 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
Z80/src/Z80.cpp
View File

@ -114,23 +114,22 @@ void EightBit::Z80::handleNMI() {
void EightBit::Z80::handleINT() { void EightBit::Z80::handleINT() {
IntelProcessor::handleINT(); IntelProcessor::handleINT();
tick(2); // 2 extra clock cycles introduced to allow the bus to settle
uint8_t data; uint8_t data;
{ {
_ActivateIORQ iorq(*this); _ActivateIORQ iorq(*this);
data = readBusDataM1(); data = readBusDataM1();
} }
di(); di();
tick(5);
switch (IM()) { switch (IM()) {
case 0: // i8080 equivalent case 0: // i8080 equivalent
IntelProcessor::execute(data); IntelProcessor::execute(data);
break; break;
case 1: case 1:
tick();
restart(7 << 3); restart(7 << 3);
break; break;
case 2: case 2:
tick(7); tick(7); // How long to allow fetching data from the device...
call(MEMPTR() = { data, IV() }); call(MEMPTR() = { data, IV() });
break; break;
default: default: