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Merge pull request #843 from polluks/patch-4

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Fixed 65C02 timing.
This commit is contained in:
Oliver Schmidt
2019-02-07 12:29:00 +01:00
committed by GitHub
parent 58484449b4 50fd96bbab
commit 3915323528
1 changed files with 12 additions and 2 deletions
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14
src/sim65/6502.c
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@@ -37,8 +37,6 @@
BBRx, BBSx, RMBx, SMBx, WAI, and STP are unsupported
* BCD flag handling equals 6502 (unchecked if bug is simulated or wrong for
6502)
* one cycle win for fetch-modify-write instructions ignored
(e.g., ROL abs,x takes only 6 cycles if no page break occurs)
*/
#include "memory.h"
@@ -629,6 +627,8 @@ static void OPC_6502_1E (void)
unsigned Val;
Cycles = 7;
Addr = MemReadWord (Regs.PC+1) + Regs.XR;
if (CPU != CPU_6502 && !PAGE_CROSS (Addr, Regs.XR))
--Cycles;
Val = MemReadByte (Addr) << 1;
MemWriteByte (Addr, (unsigned char) Val);
TEST_ZF (Val & 0xFF);
@@ -898,6 +898,8 @@ static void OPC_6502_3E (void)
unsigned Val;
Cycles = 7;
Addr = MemReadWord (Regs.PC+1) + Regs.XR;
if (CPU != CPU_6502 && !PAGE_CROSS (Addr, Regs.XR))
--Cycles;
Val = MemReadByte (Addr);
ROL (Val);
MemWriteByte (Addr, Val);
@@ -1132,6 +1134,8 @@ static void OPC_6502_5E (void)
unsigned char Val;
Cycles = 7;
Addr = MemReadWord (Regs.PC+1) + Regs.XR;
if (CPU != CPU_6502 && !PAGE_CROSS (Addr, Regs.XR))
--Cycles;
Val = MemReadByte (Addr);
SET_CF (Val & 0x01);
Val >>= 1;
@@ -1462,6 +1466,8 @@ static void OPC_6502_7E (void)
unsigned Val;
Cycles = 7;
Addr = MemReadWord (Regs.PC+1) + Regs.XR;
if (CPU != CPU_6502 && !PAGE_CROSS (Addr, Regs.XR))
--Cycles;
Val = MemReadByte (Addr);
ROR (Val);
MemWriteByte (Addr, Val);
@@ -2341,6 +2347,8 @@ static void OPC_6502_DE (void)
unsigned char Val;
Cycles = 7;
Addr = MemReadWord (Regs.PC+1) + Regs.XR;
if (CPU != CPU_6502 && !PAGE_CROSS (Addr, Regs.XR))
--Cycles;
Val = MemReadByte (Addr) - 1;
MemWriteByte (Addr, Val);
TEST_ZF (Val);
@@ -2648,6 +2656,8 @@ static void OPC_6502_FE (void)
unsigned char Val;
Cycles = 7;
Addr = MemReadWord (Regs.PC+1) + Regs.XR;
if (CPU != CPU_6502 && !PAGE_CROSS (Addr, Regs.XR))
--Cycles;
Val = MemReadByte (Addr) + 1;
MemWriteByte (Addr, Val);
TEST_ZF (Val);