djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

mimxrt/machine_uart: Implement uart.flush() and uart.txdone().

Browse Source 
uart.flush()

flush() will wait until all characters have been sent.To avoid a
permanent lock, a timeout applies depending on the size of txbuf
and the baud rate.

ret = uart.txdone()

ret is True if no transfer is in progress.
ret is False otherwise.
This commit is contained in:
robert-hh 2022-08-26 15:49:59 +02:00 committed by Damien George
parent 5466f1b0ea
commit 49e17c8bb0
1 changed files with 28 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
ports/mimxrt/machine_uart.c
View File

@ -308,17 +308,30 @@ STATIC mp_obj_t machine_uart_sendbreak(mp_obj_t self_in) {
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_sendbreak_obj, machine_uart_sendbreak);
STATIC mp_obj_t machine_uart_txdone(mp_obj_t self_in) {
machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
if (self->tx_status == kStatus_LPUART_TxIdle) {
return mp_const_true;
} else {
return mp_const_false;
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_txdone_obj, machine_uart_txdone);
STATIC const mp_rom_map_elem_t machine_uart_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_uart_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_any), MP_ROM_PTR(&machine_uart_any_obj) },
{ MP_ROM_QSTR(MP_QSTR_flush), MP_ROM_PTR(&mp_stream_flush_obj) },
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
{ MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
{ MP_ROM_QSTR(MP_QSTR_sendbreak), MP_ROM_PTR(&machine_uart_sendbreak_obj) },
{ MP_ROM_QSTR(MP_QSTR_txdone), MP_ROM_PTR(&machine_uart_txdone_obj) },
{ MP_ROM_QSTR(MP_QSTR_INV_TX), MP_ROM_INT(UART_INVERT_TX) },
{ MP_ROM_QSTR(MP_QSTR_INV_RX), MP_ROM_INT(UART_INVERT_RX) },
@ -433,6 +446,21 @@ STATIC mp_uint_t machine_uart_ioctl(mp_obj_t self_in, mp_uint_t request, mp_uint
if ((flags & MP_STREAM_POLL_WR)) {
ret |= MP_STREAM_POLL_WR;
}
} else if (request == MP_STREAM_FLUSH) {
// The timeout is estimated using the buffer size and the baudrate.
// Take the worst case assumptions at 13 bit symbol size times 2.
uint64_t timeout = (uint64_t)(3 + self->txbuf_len) * 13000000ll * 2 /
self->config.baudRate_Bps + ticks_us64();
do {
if (machine_uart_txdone((mp_obj_t)self) == mp_const_true) {
return 0;
}
MICROPY_EVENT_POLL_HOOK
} while (ticks_us64() < timeout);
*errcode = MP_ETIMEDOUT;
ret = MP_STREAM_ERROR;
} else {
*errcode = MP_EINVAL;
ret = MP_STREAM_ERROR;