X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/d1b404569fd0bdc74a3397c4ef0a5c2e5f95c835..00a4c19f8e97b088b9385af67f530c2ddecb92ce:/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