--- np2/cbus/pcm86io.c	2004/03/30 07:12:03	1.6
+++ np2/cbus/pcm86io.c	2004/03/30 08:48:46	1.7
@@ -121,25 +121,25 @@ static REG8 IOINPCALL pcm86_ia460(UINT p
 
 static REG8 IOINPCALL pcm86_ia466(UINT port) {
 
-	UINT32	nowclk;
 	UINT32	past;
+	UINT32	cnt;
+	UINT32	stepclock;
 	REG8	ret;
 
-	// こんなんでお茶濁すんなら　ちゃんと書き直しましょうね　漏れ…
-	if (!(pcm86.fifo & 0x80)) {
-		ret = 0;
-	}
-	else {
-		sound_sync();
-		nowclk = CPU_CLOCK + CPU_BASECLOCK - CPU_REMCLOCK;
-		nowclk <<= 6;
-		past = nowclk - pcm86.lastclock;
-		if (past >= pcm86.stepclock) {
-			RECALC_NOWCLKWAIT;
-			past = nowclk - pcm86.lastclock;
+	past = CPU_CLOCK + CPU_BASECLOCK - CPU_REMCLOCK;
+	past <<= 6;
+	past -= pcm86.lastclock;
+	stepclock = pcm86.stepclock;
+	if (past >= stepclock) {
+		cnt = past / stepclock;
+		pcm86.lastclock += (cnt * stepclock);
+		past -= cnt * stepclock;
+		if (pcm86.fifo & 0x80) {
+			sound_sync();
+			RECALC_NOWCLKWAIT(cnt);
 		}
-		ret = ((past << 1) >= pcm86.stepclock)?1:0;
 	}
+	ret = ((past << 1) >= stepclock)?1:0;
 	if (pcm86.virbuf >= PCM86_LOGICALBUF) {			// バッファフル
 		ret |= 0x80;
 	}