6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-11-22 12:33:29 +00:00
Code Issues Projects Releases Wiki Activity

Ensure proper return addresses are calculated for JSR.

Browse Source
This commit is contained in:
Thomas Harte 2022-05-21 14:28:44 -04:00
parent e46a3c4046
commit 2258434326
1 changed files with 7 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
Processors/68000Mk2/Implementation/68000Mk2Implementation.hpp
View File

@ -854,6 +854,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
BeginState(JSRAddressRegisterIndirect):
effective_address_[0] = registers_[8 + instruction_.reg(next_operand_)].l;
temporary_address_.l = instruction_address_.l + 2;
MoveToState(JSR_push);
//
@ -954,6 +955,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
registers_[8 + instruction_.reg(next_operand_)].l +
int16_t(prefetch_.w);
IdleBus(1); // n
temporary_address_.l = instruction_address_.l + 4;
MoveToState(JSR_push);
//
@ -995,6 +997,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
program_counter_.l - 2 +
int16_t(prefetch_.w);
IdleBus(1); // n
temporary_address_.l = instruction_address_.l + 4;
MoveToState(JSR_push);
//
@ -1036,6 +1039,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
BeginState(JSRAddressRegisterIndirectWithIndex8bitDisplacement):
effective_address_[0] = d8Xn(registers_[8 + instruction_.reg(next_operand_)].l);
IdleBus(3); // n nn
temporary_address_.l = instruction_address_.l + 4;
MoveToState(JSR_push);
//
@ -1070,6 +1074,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
BeginState(JSRProgramCounterIndirectWithIndex8bitDisplacement):
effective_address_[0] = d8Xn(program_counter_.l - 2);
IdleBus(3); // n nn
temporary_address_.l = instruction_address_.l + 4;
MoveToState(JSR_push);
#undef d8Xn
@ -1104,6 +1109,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
BeginState(JSRAbsoluteShort):
effective_address_[0] = int16_t(prefetch_.w);
IdleBus(1); // n
temporary_address_.l = instruction_address_.l + 4;
MoveToState(JSR_push);
//
@ -1141,6 +1147,7 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
BeginState(JSRAbsoluteLong):
Prefetch(); // np
effective_address_[0] = prefetch_.l;
temporary_address_.l = instruction_address_.l + 6;
MoveToState(JSR_push);
//
@ -1490,9 +1497,6 @@ void Processor<BusHandler, dtack_is_implicit, permit_overrun, signal_will_perfor
// JSR [push only; address calculation elsewhere]
//
BeginState(JSR_push):
// Grab the address of the next instruction.
temporary_address_.l = program_counter_.l - 4;
// Update the program counter and prefetch once.
program_counter_.l = effective_address_[0];
Prefetch(); // np