Cleanups to make code nicer looking. ALU subtraction fixes.

[fpgaboy.git] / insn_ldx_ahl.v

`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