Function xs_serial_constructor

modules/io/serial/pico/serial.c:109–225

}

void xs_serial_constructor(xsMachine *the)
{
	Serial serial;
	int baud;
	uint8_t hasReadable, hasWritable, format;
	xsSlot *onReadable, *onWritable;
	int err;
	int uart_id = 0;
	uint32_t transmit = UART_PIN_NO_CHANGE, receive = UART_PIN_NO_CHANGE;
	uart_inst_t *uart;

	xsmcVars(1);

	if (xsmcGet(xsVar(0), xsArg(0), xsID_transmit)) {
		transmit = builtinGetPin(the, &xsVar(0));
		if (!builtinIsPinFree(transmit))
			xsUnknownError("in use");
	}

	if (xsmcGet(xsVar(0), xsArg(0), xsID_receive)) {
		receive = builtinGetPin(the, &xsVar(0));
		if (!builtinIsPinFree(receive))
			xsUnknownError("in use");
	}
	else if (UART_PIN_NO_CHANGE == transmit)
		xsUnknownError("invalid");

	xsmcGet(xsVar(0), xsArg(0), xsID_baud);
	baud = xsmcToInteger(xsVar(0));
	if ((baud <= 0) || (baud > 20000000))
		xsRangeError("invalid baud");

	onReadable = builtinGetCallback(the, xsID_onReadable);
	onWritable = builtinGetCallback(the, xsID_onWritable);

	hasReadable = (UART_PIN_NO_CHANGE != receive) && onReadable;
	hasWritable = (UART_PIN_NO_CHANGE != transmit) && onWritable;

	builtinInitializeTarget(the);

	format = builtinInitializeFormat(the, kIOFormatBuffer);
	if ((kIOFormatNumber != format) && (kIOFormatBuffer != format))
		xsRangeError("invalid format");

	// check if port is in use
	uart_id = uart_for_pin(transmit, receive);
	if (-1 == uart_id)
		xsUnknownError("invalid");

	if (uart_in_use[uart_id])
		xsRangeError("port in use");

	uart = uart_id ? (uart_inst_t*)uart1_hw : (uart_inst_t*)uart0_hw;

	uart_init(uart, baud);
	uart_set_format(uart, 8, 1, UART_PARITY_NONE);

	serial = c_calloc((hasReadable || hasWritable) ? sizeof(SerialRecord) : offsetof(SerialRecord, the), 1);