circuitpython/ports/stm32/machine_uart.c
robert-hh 8ea6fefc6d stm32/machine_uart: Implement uart.flush() and uart.txdone().
Since uart.write() of the STM32 port waits until all bytes have
been sent, uart.flush() and uart.txdone() are implemented as empty
functions to provide API consistency.

uart.flush()

flush() will always return immediately.

ret = uart.txdone()

uart.txdone() will always return True.
2022-08-31 00:18:35 +10:00

673 lines
24 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013-2018 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include "py/runtime.h"
#include "py/stream.h"
#include "py/mperrno.h"
#include "py/mphal.h"
#include "shared/runtime/interrupt_char.h"
#include "shared/runtime/mpirq.h"
#include "uart.h"
#include "irq.h"
#include "pendsv.h"
/// \moduleref pyb
/// \class UART - duplex serial communication bus
///
/// UART implements the standard UART/USART duplex serial communications protocol. At
/// the physical level it consists of 2 lines: RX and TX. The unit of communication
/// is a character (not to be confused with a string character) which can be 8 or 9
/// bits wide.
///
/// UART objects can be created and initialised using:
///
/// from pyb import UART
///
/// uart = UART(1, 9600) # init with given baudrate
/// uart.init(9600, bits=8, parity=None, stop=1) # init with given parameters
///
/// Bits can be 8 or 9. Parity can be None, 0 (even) or 1 (odd). Stop can be 1 or 2.
///
/// A UART object acts like a stream object and reading and writing is done
/// using the standard stream methods:
///
/// uart.read(10) # read 10 characters, returns a bytes object
/// uart.read() # read all available characters
/// uart.readline() # read a line
/// uart.readinto(buf) # read and store into the given buffer
/// uart.write('abc') # write the 3 characters
///
/// Individual characters can be read/written using:
///
/// uart.readchar() # read 1 character and returns it as an integer
/// uart.writechar(42) # write 1 character
///
/// To check if there is anything to be read, use:
///
/// uart.any() # returns True if any characters waiting
STATIC void pyb_uart_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
if (!self->is_enabled) {
#if defined(LPUART1)
if (self->uart_id == PYB_LPUART_1) {
mp_printf(print, "UART('LP1')");
} else
#elif defined(LPUART2)
if (self->uart_id == PYB_LPUART_2) {
mp_printf(print, "UART('LP2')");
} else
#endif
{
mp_printf(print, "UART(%u)", self->uart_id);
}
} else {
mp_int_t bits;
uint32_t cr1 = self->uartx->CR1;
#if defined(UART_CR1_M1)
if (cr1 & UART_CR1_M1) {
bits = 7;
} else if (cr1 & UART_CR1_M0) {
bits = 9;
} else {
bits = 8;
}
#else
if (cr1 & USART_CR1_M) {
bits = 9;
} else {
bits = 8;
}
#endif
if (cr1 & USART_CR1_PCE) {
bits -= 1;
}
#if defined(LPUART1)
if (self->uart_id == PYB_LPUART_1) {
mp_printf(print, "UART('LP1', baudrate=%u, bits=%u, parity=",
uart_get_baudrate(self), bits);
} else
#endif
#if defined(LPUART2)
if (self->uart_id == PYB_LPUART_2) {
mp_printf(print, "UART('LP2', baudrate=%u, bits=%u, parity=",
uart_get_baudrate(self), bits);
} else
#endif
{
mp_printf(print, "UART(%u, baudrate=%u, bits=%u, parity=",
self->uart_id, uart_get_baudrate(self), bits);
}
if (!(cr1 & USART_CR1_PCE)) {
mp_print_str(print, "None");
} else if (!(cr1 & USART_CR1_PS)) {
mp_print_str(print, "0");
} else {
mp_print_str(print, "1");
}
uint32_t cr2 = self->uartx->CR2;
mp_printf(print, ", stop=%u, flow=",
((cr2 >> USART_CR2_STOP_Pos) & 3) == 0 ? 1 : 2);
uint32_t cr3 = self->uartx->CR3;
if (!(cr3 & (USART_CR3_CTSE | USART_CR3_RTSE))) {
mp_print_str(print, "0");
} else {
if (cr3 & USART_CR3_RTSE) {
mp_print_str(print, "RTS");
if (cr3 & USART_CR3_CTSE) {
mp_print_str(print, "|");
}
}
if (cr3 & USART_CR3_CTSE) {
mp_print_str(print, "CTS");
}
}
mp_printf(print, ", timeout=%u, timeout_char=%u, rxbuf=%u",
self->timeout, self->timeout_char,
self->read_buf_len == 0 ? 0 : self->read_buf_len - 1); // -1 to adjust for usable length of buffer
if (self->mp_irq_trigger != 0) {
mp_printf(print, "; irq=0x%x", self->mp_irq_trigger);
}
mp_print_str(print, ")");
}
}
/// \method init(baudrate, bits=8, parity=None, stop=1, *, timeout=1000, timeout_char=0, flow=0, read_buf_len=64)
///
/// Initialise the UART bus with the given parameters:
///
/// - `baudrate` is the clock rate.
/// - `bits` is the number of bits per byte, 7, 8 or 9.
/// - `parity` is the parity, `None`, 0 (even) or 1 (odd).
/// - `stop` is the number of stop bits, 1 or 2.
/// - `timeout` is the timeout in milliseconds to wait for the first character.
/// - `timeout_char` is the timeout in milliseconds to wait between characters.
/// - `flow` is RTS | CTS where RTS == 256, CTS == 512
/// - `read_buf_len` is the character length of the read buffer (0 to disable).
STATIC mp_obj_t pyb_uart_init_helper(pyb_uart_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_baudrate, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 9600} },
{ MP_QSTR_bits, MP_ARG_INT, {.u_int = 8} },
{ MP_QSTR_parity, MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
{ MP_QSTR_stop, MP_ARG_INT, {.u_int = 1} },
{ MP_QSTR_flow, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = UART_HWCONTROL_NONE} },
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_timeout_char, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_rxbuf, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_read_buf_len, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 64} }, // legacy
};
// parse args
struct {
mp_arg_val_t baudrate, bits, parity, stop, flow, timeout, timeout_char, rxbuf, read_buf_len;
} args;
mp_arg_parse_all(n_args, pos_args, kw_args,
MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t *)&args);
// baudrate
uint32_t baudrate = args.baudrate.u_int;
// parity
uint32_t bits = args.bits.u_int;
uint32_t parity;
if (args.parity.u_obj == mp_const_none) {
parity = UART_PARITY_NONE;
} else {
mp_int_t p = mp_obj_get_int(args.parity.u_obj);
parity = (p & 1) ? UART_PARITY_ODD : UART_PARITY_EVEN;
bits += 1; // STs convention has bits including parity
}
// number of bits
if (bits == 8) {
bits = UART_WORDLENGTH_8B;
} else if (bits == 9) {
bits = UART_WORDLENGTH_9B;
#ifdef UART_WORDLENGTH_7B
} else if (bits == 7) {
bits = UART_WORDLENGTH_7B;
#endif
} else {
mp_raise_ValueError(MP_ERROR_TEXT("unsupported combination of bits and parity"));
}
// stop bits
uint32_t stop;
switch (args.stop.u_int) {
case 1:
stop = UART_STOPBITS_1;
break;
default:
stop = UART_STOPBITS_2;
break;
}
// flow control
uint32_t flow = args.flow.u_int;
// Save attach_to_repl setting because uart_init will disable it.
bool attach_to_repl = self->attached_to_repl;
// init UART (if it fails, it's because the port doesn't exist)
if (!uart_init(self, baudrate, bits, parity, stop, flow)) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("UART(%d) doesn't exist"), self->uart_id);
}
// Restore attach_to_repl setting so UART still works if attached to dupterm.
uart_attach_to_repl(self, attach_to_repl);
// set timeout
self->timeout = args.timeout.u_int;
// set timeout_char
// make sure it is at least as long as a whole character (13 bits to be safe)
// minimum value is 2ms because sys-tick has a resolution of only 1ms
self->timeout_char = args.timeout_char.u_int;
uint32_t min_timeout_char = 13000 / baudrate + 2;
if (self->timeout_char < min_timeout_char) {
self->timeout_char = min_timeout_char;
}
if (self->is_static) {
// Static UARTs have fixed memory for the rxbuf and can't be reconfigured.
if (args.rxbuf.u_int >= 0) {
mp_raise_ValueError(MP_ERROR_TEXT("UART is static and rxbuf can't be changed"));
}
uart_set_rxbuf(self, self->read_buf_len, self->read_buf);
} else {
// setup the read buffer
m_del(byte, self->read_buf, self->read_buf_len << self->char_width);
if (args.rxbuf.u_int >= 0) {
// rxbuf overrides legacy read_buf_len
args.read_buf_len.u_int = args.rxbuf.u_int;
}
if (args.read_buf_len.u_int <= 0) {
// no read buffer
uart_set_rxbuf(self, 0, NULL);
} else {
// read buffer using interrupts
size_t len = args.read_buf_len.u_int + 1; // +1 to adjust for usable length of buffer
uint8_t *buf = m_new(byte, len << self->char_width);
uart_set_rxbuf(self, len, buf);
}
}
// compute actual baudrate that was configured
uint32_t actual_baudrate = uart_get_baudrate(self);
// check we could set the baudrate within 5%
uint32_t baudrate_diff;
if (actual_baudrate > baudrate) {
baudrate_diff = actual_baudrate - baudrate;
} else {
baudrate_diff = baudrate - actual_baudrate;
}
if (20 * baudrate_diff > actual_baudrate) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("set baudrate %d is not within 5%% of desired value"), actual_baudrate);
}
return mp_const_none;
}
/// \classmethod \constructor(bus, ...)
///
/// Construct a UART object on the given bus. `bus` can be 1-6, or 'XA', 'XB', 'YA', or 'YB'.
/// With no additional parameters, the UART object is created but not
/// initialised (it has the settings from the last initialisation of
/// the bus, if any). If extra arguments are given, the bus is initialised.
/// See `init` for parameters of initialisation.
///
/// The physical pins of the UART buses are:
///
/// - `UART(4)` is on `XA`: `(TX, RX) = (X1, X2) = (PA0, PA1)`
/// - `UART(1)` is on `XB`: `(TX, RX) = (X9, X10) = (PB6, PB7)`
/// - `UART(6)` is on `YA`: `(TX, RX) = (Y1, Y2) = (PC6, PC7)`
/// - `UART(3)` is on `YB`: `(TX, RX) = (Y9, Y10) = (PB10, PB11)`
/// - `UART(2)` is on: `(TX, RX) = (X3, X4) = (PA2, PA3)`
STATIC mp_obj_t pyb_uart_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
// check arguments
mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
// work out port
int uart_id = 0;
if (mp_obj_is_str(args[0])) {
const char *port = mp_obj_str_get_str(args[0]);
if (0) {
#ifdef MICROPY_HW_UART1_NAME
} else if (strcmp(port, MICROPY_HW_UART1_NAME) == 0) {
uart_id = PYB_UART_1;
#endif
#ifdef MICROPY_HW_UART2_NAME
} else if (strcmp(port, MICROPY_HW_UART2_NAME) == 0) {
uart_id = PYB_UART_2;
#endif
#ifdef MICROPY_HW_UART3_NAME
} else if (strcmp(port, MICROPY_HW_UART3_NAME) == 0) {
uart_id = PYB_UART_3;
#endif
#ifdef MICROPY_HW_UART4_NAME
} else if (strcmp(port, MICROPY_HW_UART4_NAME) == 0) {
uart_id = PYB_UART_4;
#endif
#ifdef MICROPY_HW_UART5_NAME
} else if (strcmp(port, MICROPY_HW_UART5_NAME) == 0) {
uart_id = PYB_UART_5;
#endif
#ifdef MICROPY_HW_UART6_NAME
} else if (strcmp(port, MICROPY_HW_UART6_NAME) == 0) {
uart_id = PYB_UART_6;
#endif
#ifdef MICROPY_HW_UART7_NAME
} else if (strcmp(port, MICROPY_HW_UART7_NAME) == 0) {
uart_id = PYB_UART_7;
#endif
#ifdef MICROPY_HW_UART8_NAME
} else if (strcmp(port, MICROPY_HW_UART8_NAME) == 0) {
uart_id = PYB_UART_8;
#endif
#ifdef MICROPY_HW_UART9_NAME
} else if (strcmp(port, MICROPY_HW_UART9_NAME) == 0) {
uart_id = PYB_UART_9;
#endif
#ifdef MICROPY_HW_UART10_NAME
} else if (strcmp(port, MICROPY_HW_UART10_NAME) == 0) {
uart_id = PYB_UART_10;
#endif
#ifdef MICROPY_HW_LPUART1_NAME
} else if (strcmp(port, MICROPY_HW_LPUART1_NAME) == 0) {
uart_id = PYB_LPUART_1;
#endif
#ifdef MICROPY_HW_LPUART2_NAME
} else if (strcmp(port, MICROPY_HW_LPUART2_NAME) == 0) {
uart_id = PYB_LPUART_2;
#endif
#ifdef LPUART1
} else if (strcmp(port, "LP1") == 0 && uart_exists(PYB_LPUART_1)) {
uart_id = PYB_LPUART_1;
#endif
#ifdef LPUART2
} else if (strcmp(port, "LP2") == 0 && uart_exists(PYB_LPUART_2)) {
uart_id = PYB_LPUART_2;
#endif
} else {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("UART(%s) doesn't exist"), port);
}
} else {
uart_id = mp_obj_get_int(args[0]);
if (!uart_exists(uart_id)) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("UART(%d) doesn't exist"), uart_id);
}
}
// check if the UART is reserved for system use or not
if (MICROPY_HW_UART_IS_RESERVED(uart_id)) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("UART(%d) is reserved"), uart_id);
}
pyb_uart_obj_t *self;
if (MP_STATE_PORT(pyb_uart_obj_all)[uart_id - 1] == NULL) {
// create new UART object
self = m_new0(pyb_uart_obj_t, 1);
self->base.type = &pyb_uart_type;
self->uart_id = uart_id;
MP_STATE_PORT(pyb_uart_obj_all)[uart_id - 1] = self;
} else {
// reference existing UART object
self = MP_STATE_PORT(pyb_uart_obj_all)[uart_id - 1];
}
if (n_args > 1 || n_kw > 0) {
// start the peripheral
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
pyb_uart_init_helper(self, n_args - 1, args + 1, &kw_args);
}
return MP_OBJ_FROM_PTR(self);
}
STATIC mp_obj_t pyb_uart_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
return pyb_uart_init_helper(MP_OBJ_TO_PTR(args[0]), n_args - 1, args + 1, kw_args);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_uart_init_obj, 1, pyb_uart_init);
/// \method deinit()
/// Turn off the UART bus.
STATIC mp_obj_t pyb_uart_deinit(mp_obj_t self_in) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
uart_deinit(self);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_deinit_obj, pyb_uart_deinit);
/// \method any()
/// Return `True` if any characters waiting, else `False`.
STATIC mp_obj_t pyb_uart_any(mp_obj_t self_in) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
return MP_OBJ_NEW_SMALL_INT(uart_rx_any(self));
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_any_obj, pyb_uart_any);
/// \method writechar(char)
/// Write a single character on the bus. `char` is an integer to write.
/// Return value: `None`.
STATIC mp_obj_t pyb_uart_writechar(mp_obj_t self_in, mp_obj_t char_in) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
// get the character to write (might be 9 bits)
uint16_t data = mp_obj_get_int(char_in);
// write the character
int errcode;
if (uart_tx_wait(self, self->timeout)) {
uart_tx_data(self, &data, 1, &errcode);
} else {
errcode = MP_ETIMEDOUT;
}
if (errcode != 0) {
mp_raise_OSError(errcode);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_uart_writechar_obj, pyb_uart_writechar);
/// \method readchar()
/// Receive a single character on the bus.
/// Return value: The character read, as an integer. Returns -1 on timeout.
STATIC mp_obj_t pyb_uart_readchar(mp_obj_t self_in) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
if (uart_rx_wait(self, self->timeout)) {
return MP_OBJ_NEW_SMALL_INT(uart_rx_char(self));
} else {
// return -1 on timeout
return MP_OBJ_NEW_SMALL_INT(-1);
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_readchar_obj, pyb_uart_readchar);
// uart.sendbreak()
STATIC mp_obj_t pyb_uart_sendbreak(mp_obj_t self_in) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
#if defined(STM32F0) || defined(STM32F7) || defined(STM32G0) || defined(STM32G4) || defined(STM32H7) || defined(STM32L0) || defined(STM32L4) || defined(STM32WB) || defined(STM32WL)
self->uartx->RQR = USART_RQR_SBKRQ; // write-only register
#else
self->uartx->CR1 |= USART_CR1_SBK;
#endif
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_sendbreak_obj, pyb_uart_sendbreak);
// irq(handler, trigger, hard)
STATIC mp_obj_t pyb_uart_irq(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
mp_arg_val_t args[MP_IRQ_ARG_INIT_NUM_ARGS];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_IRQ_ARG_INIT_NUM_ARGS, mp_irq_init_args, args);
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
if (self->mp_irq_obj == NULL) {
self->mp_irq_trigger = 0;
self->mp_irq_obj = mp_irq_new(&uart_irq_methods, MP_OBJ_FROM_PTR(self));
}
if (n_args > 1 || kw_args->used != 0) {
// Check the handler
mp_obj_t handler = args[MP_IRQ_ARG_INIT_handler].u_obj;
if (handler != mp_const_none && !mp_obj_is_callable(handler)) {
mp_raise_ValueError(MP_ERROR_TEXT("handler must be None or callable"));
}
// Check the trigger
mp_uint_t trigger = args[MP_IRQ_ARG_INIT_trigger].u_int;
mp_uint_t not_supported = trigger & ~MP_UART_ALLOWED_FLAGS;
if (trigger != 0 && not_supported) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("trigger 0x%08x unsupported"), not_supported);
}
// Reconfigure user IRQs
uart_irq_config(self, false);
self->mp_irq_obj->handler = handler;
self->mp_irq_obj->ishard = args[MP_IRQ_ARG_INIT_hard].u_bool;
self->mp_irq_trigger = trigger;
uart_irq_config(self, true);
}
return MP_OBJ_FROM_PTR(self->mp_irq_obj);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_uart_irq_obj, 1, pyb_uart_irq);
// Since uart.write() waits up to the last byte, uart.txdone() always returns True.
STATIC mp_obj_t machine_uart_txdone(mp_obj_t self_in) {
return mp_const_true;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_txdone_obj, machine_uart_txdone);
STATIC const mp_rom_map_elem_t pyb_uart_locals_dict_table[] = {
// instance methods
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&pyb_uart_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&pyb_uart_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_any), MP_ROM_PTR(&pyb_uart_any_obj) },
/// \method read([nbytes])
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
/// \method readline()
{ MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj)},
/// \method readinto(buf[, nbytes])
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
/// \method write(buf)
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
{ MP_ROM_QSTR(MP_QSTR_flush), MP_ROM_PTR(&mp_stream_flush_obj) },
{ MP_ROM_QSTR(MP_QSTR_irq), MP_ROM_PTR(&pyb_uart_irq_obj) },
{ MP_ROM_QSTR(MP_QSTR_writechar), MP_ROM_PTR(&pyb_uart_writechar_obj) },
{ MP_ROM_QSTR(MP_QSTR_readchar), MP_ROM_PTR(&pyb_uart_readchar_obj) },
{ MP_ROM_QSTR(MP_QSTR_sendbreak), MP_ROM_PTR(&pyb_uart_sendbreak_obj) },
{ MP_ROM_QSTR(MP_QSTR_txdone), MP_ROM_PTR(&machine_uart_txdone_obj) },
// class constants
{ MP_ROM_QSTR(MP_QSTR_RTS), MP_ROM_INT(UART_HWCONTROL_RTS) },
{ MP_ROM_QSTR(MP_QSTR_CTS), MP_ROM_INT(UART_HWCONTROL_CTS) },
// IRQ flags
{ MP_ROM_QSTR(MP_QSTR_IRQ_RXIDLE), MP_ROM_INT(UART_FLAG_IDLE) },
};
STATIC MP_DEFINE_CONST_DICT(pyb_uart_locals_dict, pyb_uart_locals_dict_table);
STATIC mp_uint_t pyb_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t size, int *errcode) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
byte *buf = buf_in;
// check that size is a multiple of character width
if (size & self->char_width) {
*errcode = MP_EIO;
return MP_STREAM_ERROR;
}
// convert byte size to char size
size >>= self->char_width;
// make sure we want at least 1 char
if (size == 0) {
return 0;
}
// wait for first char to become available
if (!uart_rx_wait(self, self->timeout)) {
// return EAGAIN error to indicate non-blocking (then read() method returns None)
*errcode = MP_EAGAIN;
return MP_STREAM_ERROR;
}
// read the data
byte *orig_buf = buf;
for (;;) {
int data = uart_rx_char(self);
if (self->char_width == CHAR_WIDTH_9BIT) {
*(uint16_t *)buf = data;
buf += 2;
} else {
*buf++ = data;
}
if (--size == 0 || !uart_rx_wait(self, self->timeout_char)) {
// return number of bytes read
return buf - orig_buf;
}
}
}
STATIC mp_uint_t pyb_uart_write(mp_obj_t self_in, const void *buf_in, mp_uint_t size, int *errcode) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
const byte *buf = buf_in;
// check that size is a multiple of character width
if (size & self->char_width) {
*errcode = MP_EIO;
return MP_STREAM_ERROR;
}
// wait to be able to write the first character. EAGAIN causes write to return None
if (!uart_tx_wait(self, self->timeout)) {
*errcode = MP_EAGAIN;
return MP_STREAM_ERROR;
}
// write the data
size_t num_tx = uart_tx_data(self, buf, size >> self->char_width, errcode);
if (*errcode == 0 || *errcode == MP_ETIMEDOUT) {
// return number of bytes written, even if there was a timeout
return num_tx << self->char_width;
} else {
return MP_STREAM_ERROR;
}
}
STATIC mp_uint_t pyb_uart_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
pyb_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
mp_uint_t ret;
if (request == MP_STREAM_POLL) {
uintptr_t flags = arg;
ret = 0;
if ((flags & MP_STREAM_POLL_RD) && uart_rx_any(self)) {
ret |= MP_STREAM_POLL_RD;
}
if ((flags & MP_STREAM_POLL_WR) && uart_tx_avail(self)) {
ret |= MP_STREAM_POLL_WR;
}
} else if (request == MP_STREAM_FLUSH) {
// Since uart.write() waits up to the last byte, uart.flush() always succeds.
ret = 0;
} else {
*errcode = MP_EINVAL;
ret = MP_STREAM_ERROR;
}
return ret;
}
STATIC const mp_stream_p_t uart_stream_p = {
.read = pyb_uart_read,
.write = pyb_uart_write,
.ioctl = pyb_uart_ioctl,
.is_text = false,
};
const mp_obj_type_t pyb_uart_type = {
{ &mp_type_type },
.name = MP_QSTR_UART,
.print = pyb_uart_print,
.make_new = pyb_uart_make_new,
.getiter = mp_identity_getiter,
.iternext = mp_stream_unbuffered_iter,
.protocol = &uart_stream_p,
.locals_dict = (mp_obj_dict_t *)&pyb_uart_locals_dict,
};