--- nono/vm/spc.cpp	2026/04/29 17:04:50	1.1.1.8
+++ nono/vm/spc.cpp	2026/04/29 17:04:53	1.1.1.9
@@ -949,10 +949,10 @@ SPCDevice::GetSSTS() const
 	if (spc.tc == 0) {	// TC がゼロか
 		data |= SPC::SSTS_TC_ZERO;
 	}
-	if (spc.dreg.Length() == 8) {
+	if (spc.dreg.IsFull()) {
 		data |= SPC::SSTS_DREG_FULL;
 	}
-	if (spc.dreg.Length() == 0) {
+	if (spc.dreg.Empty()) {
 		data |= SPC::SSTS_DREG_EMPTY;
 	}