From: Joshua Wise <joshua@rebirth.joshuawise.com>
Date: Fri, 9 May 2008 09:34:07 +0000 (-0400)
Subject: Cut 1 at ADD HL,...
X-Git-Url: http://git.joshuawise.com/fpgaboy.git/commitdiff_plain/00a4c19f8e97b088b9385af67f530c2ddecb92ce?ds=inline

Cut 1 at ADD HL,...
---

diff --git a/GBZ80Core.v b/GBZ80Core.v
index 29aab52..053df4a 100644
--- a/GBZ80Core.v
+++ b/GBZ80Core.v
@@ -79,6 +79,7 @@
 `define INSN_BIT		9'b101xxxxxx
 `define INSN_RES		9'b110xxxxxx
 `define INSN_SET		9'b111xxxxxx
+`define INSN_ADD_HL		9'b000xx1001
 
 `define INSN_cc_NZ		2'b00
 `define INSN_cc_Z		2'b01
diff --git a/Makefile b/Makefile
index 5e50da8..40ea542 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@ VLOGS_ALL = $(VLOGS) insn_call-callcc.v insn_incdec16.v insn_jr-jrcc.v \
 	CPUDCM.v insn_alu_a.v insn_halt.v insn_jp-jpcc.v insn_ld_hl_reg.v \
 	insn_ld_reg_imm8.v insn_ldx_ahl.v insn_push_reg.v insn_vop_intr.v \
 	insn_ldm8_a.v insn_ldm16_a.v insn_ldbcde_a.v insn_alu_ext.v \
-	insn_bit.v insn_two_byte.v insn_incdec_reg8.v
+	insn_bit.v insn_two_byte.v insn_incdec_reg8.v insn_add_hl.v
 
 all: CoreTop.svf
 
diff --git a/allinsns.v b/allinsns.v
index 6c1c487..dfdf04f 100644
--- a/allinsns.v
+++ b/allinsns.v
@@ -29,3 +29,4 @@
 `include "insn_two_byte.v"
 `include "insn_bit.v"
 `include "insn_alu_ext.v"
+`include "insn_add_hl.v"
diff --git a/insn_add_hl.v b/insn_add_hl.v
new file mode 100644
index 0000000..8ff25f4
--- /dev/null
+++ b/insn_add_hl.v
@@ -0,0 +1,33 @@
+`ifdef EXECUTE
+	`INSN_ADD_HL: begin
+		case (cycle)
+		0:	case (opcode[5:4])
+			`INSN_reg16_BC:	{tmp,tmp2} <= `_BC;
+			`INSN_reg16_DE:	{tmp,tmp2} <= `_DE;
+			`INSN_reg16_HL:	{tmp,tmp2} <= `_HL;
+			`INSN_reg16_SP:	{tmp,tmp2} <= `_SP;
+			endcase
+		1:	begin
+				`EXEC_INC_PC
+				`EXEC_NEWCYCLE
+			end
+		endcase
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_ADD_HL: begin
+		case (cycle)
+		0:	{tmp,tmp2} <= `_HL + {tmp,tmp2};
+		1:	begin
+				`_F <=	{ /* Z */ `_F[7],
+					  /* N */ 1'b0,
+					  /* H */ (({`_HL} + {tmp,tmp2}) & 16'h1000) ? 1'b1 : 1'b0,
+					  /* C */ (({1'b0,`_HL} + {1'b0,tmp,tmp2}) >> 16 == 1) ? 1'b1 : 1'b0,
+					  `_F[3:0]
+					};
+				`_HL <= {tmp, tmp2};
+			end
+		endcase
+	end
+`endif
diff --git a/opcodes b/opcodes
index 09f68fb..451a6b6 100644
--- a/opcodes
+++ b/opcodes
@@ -8,11 +8,7 @@ imm16 = 16-bit immediate value
 
 bits         insn                 notes
 0000 1000    LD    16m16,SP      loads SP
-0000 1001    ADD   HL,   BC
 0001 0000    STOP
-0001 1001    ADD   HL,   DE
-0010 1001    ADD   HL,   HL
-0011 1001    ADD   HL,   SP
 0111 0110    HALT                 Danger! Helvetica!
 1100 1011    -     -     -        see two-byte opcodes below
 1110 1000    ADD   SP,   imm8