X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/eb0f2fe1637a4c6b4532ae08ff7b0af3bf39aef0..3ad960bdb71efcbb1dfd436163085da0d70eb699:/insn_ldx_ahl.v

diff --git a/insn_ldx_ahl.v b/insn_ldx_ahl.v
new file mode 100644
index 0000000..a16d6ba
--- /dev/null
+++ b/insn_ldx_ahl.v
@@ -0,0 +1,35 @@
+`ifdef EXECUTE
+	`INSN_LDx_AHL: begin
+		case (cycle)
+		0:	begin
+				address <= {registers[`REG_H],registers[`REG_L]};
+				if (opcode[3]) begin	// LDx A, (HL)
+					rd <= 1;
+				end else begin
+					wr <= 1;
+					wdata <= registers[`REG_A];
+				end
+			end
+		1:	begin
+				`EXEC_NEWCYCLE;
+				`EXEC_INC_PC;
+			end
+		endcase
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_LDx_AHL: begin
+		case (cycle)
+		0:	begin /* Type F */ end
+		1:	begin
+				if (opcode[3])
+					registers[`REG_A] <= rdata;
+				{registers[`REG_H],registers[`REG_L]} <=
+					opcode[4] ? // if set, LDD, else LDI
+					({registers[`REG_H],registers[`REG_L]} - 1) :
+					({registers[`REG_H],registers[`REG_L]} + 1);
+			end
+		endcase
+	end
+`endif