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-rw-r--r--cpu.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/cpu.c b/cpu.c
index 66dbd4c..5d36d37 100644
--- a/cpu.c
+++ b/cpu.c
@@ -218,11 +218,12 @@ adc(uint8_t arg)
uint16_t sum; // 16-bit sum makes it easier to determine carry flag
sum = regs.a + arg + regs.status.carry;
- regs.a = sum & 0xFF;
regs.status.carry = sum > 0xFF;
/* overflow flag formula: https://stackoverflow.com/a/29224684 */
regs.status.overflow = (~(regs.a ^ arg) & (regs.a ^ sum) & 0x80) != 0;
+ regs.a = sum & 0xFF;
+
STATUS_UPDATE_ZERO(regs.a);
STATUS_UPDATE_NEGATIVE(regs.a);
}