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This commit is contained in:
redcode
2022-05-17 12:59:20 +02:00
parent 028f50cbde
commit d9c073b875
1 changed files with 0 additions and 19 deletions
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sources/Z80.c
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@@ -2241,12 +2241,6 @@ Z80_API zusize z80_run(Z80 *self, zusize cycles)
# ifdef Z80_WITH_SPECIAL_RESET_SIGNAL
PC >>= REQUEST & Z80_REQUEST_CLEAR_PC;
/*----------------------------.
| RESET -> RESET |
| NMI -> REJECT_NMI |
| SPECIAL_RESET -> CLEAR_PC |
'----------------------------*/
REQUEST = (REQUEST & (Z80_REQUEST_ANY_RESET | Z80_REQUEST_NMI)) >> 1;
# else
REQUEST =
@@ -2272,19 +2266,6 @@ Z80_API zusize z80_run(Z80 *self, zusize cycles)
| following "ei" is executed. This is so that ISRs can return without the |
| danger of being interrupted immediately after re-enabling interrupts if |
| the /INT line is still active, which could cause a stack overflow. |
| |
| This behavior is also present in all forms of the the "reti" and "retn"
| instructions.
| interrupt acceptance for one instruction, but this only occurs when IFF1 |
| and IFF2 have different states prior to the execution of either of these |
| instructions. This was first documented by Andre Weissflog (AKA Floh) in |
| 2021 [1], and was later rediscovered by Manuel Sainz de Baranda y Goñi |
| (AKA ZjoyKiLer) in 2022 [2,3]. |
| |
| References: |
| 1. https://floooh.github.io/2021/12/17/cycle-stepped-z80.html
| 2. https://spectrumcomputing.co.uk/forums/viewtopic.php?p=91342#p91342 |
| 3. https://stardot.org.uk/forums/viewtopic.php?t=24662 |
'=========================================================================*/
else if (
# ifdef Z80_WITH_SPECIAL_RESET_SIGNAL