diff --git a/src/gbemu/cpu.c b/src/gbemu/cpu.c
index 4c92384..d097d80 100644
--- a/src/gbemu/cpu.c
+++ b/src/gbemu/cpu.c
@@ -372,7 +372,7 @@ void lr35902_cycle(struct lr35902_state *cpu)
 		INC_8(cpu, cpu->c);
 		break;
 	case 0x0d: /* DEC C */
-		DEC_8(cpu, cpu->d);
+		DEC_8(cpu, cpu->c);
 		break;
 	case 0x0e: /* LD C, d8 */
 		LD_D8(cpu, cpu->c);