emu_nes

commit 858cbfba48145ff9303a4127cb73911fc8904462
parent 76b9059b2e299dca5a96cf94f21038002f4dad3a
Author: vin <git@vineetk.net>
Date:   Sun,  9 Jun 2024 15:35:31 +0530

fix potential adc overflow flag bug

Diffstat:
M
cpu.c
 | 
2
+-

1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/cpu.c b/cpu.c
@@ -120,7 +120,7 @@ adc(uint8_t arg)
 
 	regs.status.carry = sum > 0xFF;
 	/* overflow flag formula: https://stackoverflow.com/a/29224684 */
-	regs.status.overflow = ~(regs.a ^ arg) & (regs.a ^ sum) & 0x80;
+	regs.status.overflow = (~(regs.a ^ arg) & (regs.a ^ sum) & 0x80) > 0;
 	STATUS_UPDATE_ZERO(regs.a);
 	STATUS_UPDATE_NEGATIVE(regs.a);
 }