# HG changeset patch
# User Michael Pavone <pavone@retrodev.com>
# Date 1432704150 25200
# Node ID 8972378e314fe1e53e8554d5490f039886767308
# Parent  043393b79e288de6af9daee217c955c77c379e23
Fix register to operator mapping for channel 3 special mode

diff -r 043393b79e28 -r 8972378e314f ym2612.c
--- a/ym2612.c	Tue May 26 20:00:50 2015 -0700
+++ b/ym2612.c	Tue May 26 22:22:30 2015 -0700
@@ -585,14 +585,16 @@
 	ym_channel * channel = context->channels + chan_num;
 	uint32_t inc, detune;
 	if (chan_num == 2 && context->ch3_mode && (op < (2*4 + 3))) {
-		inc = context->ch3_supp[op-2*4].fnum;
-		if (!context->ch3_supp[op-2*4].block) {
+		//supplemental fnum registers are in a different order than normal slot paramters
+		int index = (op-2*4) ^ 2;
+		inc = context->ch3_supp[index].fnum;
+		if (!context->ch3_supp[index].block) {
 			inc >>= 1;
 		} else {
-			inc <<= (context->ch3_supp[op-2*4].block-1);
+			inc <<= (context->ch3_supp[index].block-1);
 		}
 		//detune
-		detune = detune_table[context->ch3_supp[op-2*4].keycode][operator->detune & 0x3];
+		detune = detune_table[context->ch3_supp[index].keycode][operator->detune & 0x3];
 	} else {
 		inc = channel->fnum;
 		if (!channel->block) {