From: Joshua Wise <joshua@rebirth.joshuawise.com>
Date: Fri, 4 Apr 2008 06:10:58 +0000 (-0400)
Subject: Yay. Fix retcc. Comparing against an x value - great idea, or greatest idea?
X-Git-Url: http://git.joshuawise.com/fpgaboy.git/commitdiff_plain/f26748f71f3f39de15a1c07f95c15f8c4481f452?hp=611e4a90d4f4c5b5e2cadde0da57639bfbaca6a8

Yay. Fix retcc. Comparing against an x value - great idea, or greatest idea?
---

diff --git a/FPGABoy.ise b/FPGABoy.ise
index b09f383..1d807e9 100644
Binary files a/FPGABoy.ise and b/FPGABoy.ise differ
diff --git a/GBZ80Core.v b/GBZ80Core.v
index cd7f4d1..3cd46e3 100644
--- a/GBZ80Core.v
+++ b/GBZ80Core.v
@@ -401,7 +401,7 @@ module GBZ80Core(
 					end
 				endcase
 			end
-			`INSN_RET: begin
+			`INSN_RET,`INSN_RETCC: begin
 				case (cycle)
 				0:	begin
 						rd <= 1;
@@ -409,8 +409,6 @@ module GBZ80Core(
 					end
 				1:	begin	// SPECIAL CASE: cycle does NOT increase linearly with ret!
 						`EXEC_INC_PC;
-						if (opcode != `INSN_RETCC)
-							$stop;
 						case (opcode[4:3])	// cycle 1 is skipped if we are not retcc
 						`INSN_cc_NZ:	if (registers[`REG_F][7]) begin `EXEC_NEWCYCLE; end
 						`INSN_cc_Z:		if (~registers[`REG_F][7]) begin `EXEC_NEWCYCLE; end
@@ -794,7 +792,7 @@ module GBZ80Core(
 			end
 			`INSN_RET,`INSN_RETCC: begin
 				case (cycle)
-				0:	if (opcode != `INSN_RETCC)
+				0:	if (opcode[0])	// i.e., not RETCC
 						cycle <= 1;	// Skip cycle 1; it gets incremented on the next round.
 				1: begin /* Nothing need happen here. */ end
 				2:	registers[`REG_PCL] <= rdata;
diff --git a/rom.asm b/rom.asm
index aa070ff..d650855 100644
--- a/rom.asm
+++ b/rom.asm
@@ -212,7 +212,7 @@ insntest:
 .cplfail:
 	db "CPL",0
 .testfailed:
-	db "test failed.",$0D,$0A,0
+	db " test failed.",$0D,$0A,0
 .ok:
 	db "OK!",$0D,$0A,0
 
@@ -233,9 +233,6 @@ puts:
 	ld a, [hli]
 	ld b, $00
 	cp b
-	jr z, .done
+	ret z
 	call putc
 	jr puts
-.done:
-	ret
-