djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
1559a97810
circuitpython/stmhal/uart.c
Damien George 4ef67d30f1 stmhal: Implement support for RTS/CTS hardware flow control in UART. 
This is experimental support.  API is subject to changes.  RTS/CTS
available on UART(2) and UART(3) only.  Use as:

    uart = pyb.UART(2, 9600, flow=pyb.UART.RTS | pyb.UART.CTS)
2014-10-31 00:40:57 +00:00

724 lines
25 KiB
C
Raw Blame History

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 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 <errno.h>
#include "mpconfig.h"
#include "nlr.h"
#include "misc.h"
#include "qstr.h"
#include "obj.h"
#include "runtime.h"
#include "stream.h"
#include "uart.h"
#include "pybioctl.h"
#include MICROPY_HAL_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.readall() # 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
#define CHAR_WIDTH_8BIT (0)
#define CHAR_WIDTH_9BIT (1)
struct _pyb_uart_obj_t {
mp_obj_base_t base;
pyb_uart_t uart_id;
bool is_enabled;
UART_HandleTypeDef uart;
IRQn_Type irqn;
uint16_t timeout; // timeout waiting for first char
uint16_t timeout_char; // timeout waiting between chars
uint16_t char_width; // 0 for 7,8 bit chars, 1 for 9 bit chars
uint16_t read_buf_len; // len in chars; buf can hold len-1 chars
volatile uint16_t read_buf_head; // indexes first empty slot
uint16_t read_buf_tail; // indexes first full slot (not full if equals head)
byte *read_buf; // byte or uint16_t, depending on char size
};
// pointers to all UART objects (if they have been created)
STATIC pyb_uart_obj_t *pyb_uart_obj_all[6];
STATIC mp_obj_t pyb_uart_deinit(mp_obj_t self_in);
void uart_init0(void) {
for (int i = 0; i < MP_ARRAY_SIZE(pyb_uart_obj_all); i++) {
pyb_uart_obj_all[i] = NULL;
}
}
// unregister all interrupt sources
void uart_deinit(void) {
for (int i = 0; i < MP_ARRAY_SIZE(pyb_uart_obj_all); i++) {
pyb_uart_obj_t *uart_obj = pyb_uart_obj_all[i];
if (uart_obj != NULL) {
pyb_uart_deinit(uart_obj);
}
}
}
// assumes Init parameters have been set up correctly
STATIC bool uart_init2(pyb_uart_obj_t *uart_obj) {
USART_TypeDef *UARTx;
IRQn_Type irqn;
uint32_t GPIO_Pin;
uint8_t GPIO_AF_UARTx = 0;
GPIO_TypeDef* GPIO_Port = NULL;
switch (uart_obj->uart_id) {
// USART1 is on PA9/PA10 (CK on PA8), PB6/PB7
case PYB_UART_1:
UARTx = USART1;
irqn = USART1_IRQn;
GPIO_AF_UARTx = GPIO_AF7_USART1;
#if defined (PYBV4) || defined(PYBV10)
GPIO_Port = GPIOB;
GPIO_Pin = GPIO_PIN_6 | GPIO_PIN_7;
#else
GPIO_Port = GPIOA;
GPIO_Pin = GPIO_PIN_9 | GPIO_PIN_10;
#endif
__USART1_CLK_ENABLE();
break;
// USART2 is on PA2/PA3 (CTS,RTS,CK on PA0,PA1,PA4), PD5/PD6 (CK on PD7)
case PYB_UART_2:
UARTx = USART2;
irqn = USART2_IRQn;
GPIO_AF_UARTx = GPIO_AF7_USART2;
GPIO_Port = GPIOA;
GPIO_Pin = GPIO_PIN_2 | GPIO_PIN_3;
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_RTS) {
GPIO_Pin |= GPIO_PIN_1;
}
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS) {
GPIO_Pin |= GPIO_PIN_0;
}
__USART2_CLK_ENABLE();
break;
// USART3 is on PB10/PB11 (CK,CTS,RTS on PB12,PB13,PB14), PC10/PC11 (CK on PC12), PD8/PD9 (CK on PD10)
case PYB_UART_3:
UARTx = USART3;
irqn = USART3_IRQn;
GPIO_AF_UARTx = GPIO_AF7_USART3;
#if defined(PYBV3) || defined(PYBV4) | defined(PYBV10)
GPIO_Port = GPIOB;
GPIO_Pin = GPIO_PIN_10 | GPIO_PIN_11;
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_RTS) {
GPIO_Pin |= GPIO_PIN_14;
}
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS) {
GPIO_Pin |= GPIO_PIN_13;
}
#else
GPIO_Port = GPIOD;
GPIO_Pin = GPIO_PIN_8 | GPIO_PIN_9;
#endif
__USART3_CLK_ENABLE();
break;
// UART4 is on PA0/PA1, PC10/PC11
case PYB_UART_4:
UARTx = UART4;
irqn = UART4_IRQn;
GPIO_AF_UARTx = GPIO_AF8_UART4;
GPIO_Port = GPIOA;
GPIO_Pin = GPIO_PIN_0 | GPIO_PIN_1;
__UART4_CLK_ENABLE();
break;
// USART6 is on PC6/PC7 (CK on PC8)
case PYB_UART_6:
UARTx = USART6;
irqn = USART6_IRQn;
GPIO_AF_UARTx = GPIO_AF8_USART6;
GPIO_Port = GPIOC;
GPIO_Pin = GPIO_PIN_6 | GPIO_PIN_7;
__USART6_CLK_ENABLE();
break;
default:
return false;
}
uart_obj->irqn = irqn;
uart_obj->uart.Instance = UARTx;
// init GPIO
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Pin = GPIO_Pin;
GPIO_InitStructure.Speed = GPIO_SPEED_HIGH;
GPIO_InitStructure.Mode = GPIO_MODE_AF_PP;
GPIO_InitStructure.Pull = GPIO_PULLUP;
GPIO_InitStructure.Alternate = GPIO_AF_UARTx;
HAL_GPIO_Init(GPIO_Port, &GPIO_InitStructure);
// init UARTx
HAL_UART_Init(&uart_obj->uart);
uart_obj->is_enabled = true;
return true;
}
/* obsolete and unused
bool uart_init(pyb_uart_obj_t *uart_obj, uint32_t baudrate) {
UART_HandleTypeDef *uh = &uart_obj->uart;
memset(uh, 0, sizeof(*uh));
uh->Init.BaudRate = baudrate;
uh->Init.WordLength = UART_WORDLENGTH_8B;
uh->Init.StopBits = UART_STOPBITS_1;
uh->Init.Parity = UART_PARITY_NONE;
uh->Init.Mode = UART_MODE_TX_RX;
uh->Init.HwFlowCtl = UART_HWCONTROL_NONE;
uh->Init.OverSampling = UART_OVERSAMPLING_16;
return uart_init2(uart_obj);
}
*/
bool uart_rx_any(pyb_uart_obj_t *self) {
return self->read_buf_tail != self->read_buf_head
|| __HAL_UART_GET_FLAG(&self->uart, UART_FLAG_RXNE) != RESET;
}
// Waits at most timeout milliseconds for at least 1 char to become ready for
// reading (from buf or for direct reading).
// Returns true if something available, false if not.
STATIC bool uart_rx_wait(pyb_uart_obj_t *self, uint32_t timeout) {
uint32_t start = HAL_GetTick();
for (;;) {
if (self->read_buf_tail != self->read_buf_head || __HAL_UART_GET_FLAG(&self->uart, UART_FLAG_RXNE) != RESET) {
return true; // have at least 1 char ready for reading
}
if (HAL_GetTick() - start >= timeout) {
return false; // timeout
}
__WFI();
}
}
// assumes there is a character available
int uart_rx_char(pyb_uart_obj_t *self) {
if (self->read_buf_tail != self->read_buf_head) {
// buffering via IRQ
int data;
if (self->char_width == CHAR_WIDTH_9BIT) {
data = ((uint16_t*)self->read_buf)[self->read_buf_tail];
} else {
data = self->read_buf[self->read_buf_tail];
}
self->read_buf_tail = (self->read_buf_tail + 1) % self->read_buf_len;
return data;
} else {
// no buffering
return self->uart.Instance->DR;
}
}
STATIC void uart_tx_char(pyb_uart_obj_t *uart_obj, int c) {
uint8_t ch = c;
HAL_UART_Transmit(&uart_obj->uart, &ch, 1, uart_obj->timeout);
}
void uart_tx_strn(pyb_uart_obj_t *uart_obj, const char *str, uint len) {
HAL_UART_Transmit(&uart_obj->uart, (uint8_t*)str, len, uart_obj->timeout);
}
void uart_tx_strn_cooked(pyb_uart_obj_t *uart_obj, const char *str, uint len) {
for (const char *top = str + len; str < top; str++) {
if (*str == '\n') {
uart_tx_char(uart_obj, '\r');
}
uart_tx_char(uart_obj, *str);
}
}
// this IRQ handler is set up to handle RXNE interrupts only
void uart_irq_handler(mp_uint_t uart_id) {
// get the uart object
pyb_uart_obj_t *self = pyb_uart_obj_all[uart_id - 1];
if (self == NULL) {
// UART object has not been set, so we can't do anything, not
// even disable the IRQ. This should never happen.
return;
}
if (__HAL_UART_GET_FLAG(&self->uart, UART_FLAG_RXNE) != RESET) {
int data = self->uart.Instance->DR; // clears UART_FLAG_RXNE
if (self->read_buf_len != 0) {
uint16_t next_head = (self->read_buf_head + 1) % self->read_buf_len;
if (next_head != self->read_buf_tail) {
// only store data if room in buf
if (self->char_width == CHAR_WIDTH_9BIT) {
((uint16_t*)self->read_buf)[self->read_buf_head] = data;
} else {
self->read_buf[self->read_buf_head] = data;
}
self->read_buf_head = next_head;
}
} else {
// TODO set flag for buffer overflow
}
}
}
/******************************************************************************/
/* Micro Python bindings */
STATIC void pyb_uart_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_uart_obj_t *self = self_in;
if (!self->is_enabled) {
print(env, "UART(%u)", self->uart_id);
} else {
print(env, "UART(%u, baudrate=%u, bits=%u, parity=",
self->uart_id, self->uart.Init.BaudRate,
self->uart.Init.WordLength == UART_WORDLENGTH_8B ? 8 : 9);
if (self->uart.Init.Parity == UART_PARITY_NONE) {
print(env, "None");
} else {
print(env, "%u", self->uart.Init.Parity == UART_PARITY_EVEN ? 0 : 1);
}
print(env, ", stop=%u, timeout=%u, timeout_char=%u, read_buf_len=%u)",
self->uart.Init.StopBits == UART_STOPBITS_1 ? 1 : 2,
self->timeout, self->timeout_char, self->read_buf_len);
}
}
/// \method init(baudrate, bits=8, parity=None, stop=1, *, timeout=1000, timeout_char=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, 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.
/// - `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, mp_uint_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_obj = mp_const_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 = 1000} },
{ MP_QSTR_timeout_char, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_read_buf_len, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 64} },
};
// parse args
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// set the UART configuration values
memset(&self->uart, 0, sizeof(self->uart));
UART_InitTypeDef *init = &self->uart.Init;
init->BaudRate = args[0].u_int;
init->WordLength = args[1].u_int == 8 ? UART_WORDLENGTH_8B : UART_WORDLENGTH_9B;
if (args[2].u_obj == mp_const_none) {
init->Parity = UART_PARITY_NONE;
} else {
mp_int_t parity = mp_obj_get_int(args[2].u_obj);
init->Parity = (parity & 1) ? UART_PARITY_ODD : UART_PARITY_EVEN;
}
switch (args[3].u_int) {
case 1: init->StopBits = UART_STOPBITS_1; break;
default: init->StopBits = UART_STOPBITS_2; break;
}
init->Mode = UART_MODE_TX_RX;
init->HwFlowCtl = args[4].u_int;
init->OverSampling = UART_OVERSAMPLING_16;
// init UART (if it fails, it's because the port doesn't exist)
if (!uart_init2(self)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%d) does not exist", self->uart_id));
}
// set timeouts
self->timeout = args[5].u_int;
self->timeout_char = args[6].u_int;
// setup the read buffer
m_del(byte, self->read_buf, self->read_buf_len << self->char_width);
if (init->WordLength == UART_WORDLENGTH_9B && init->Parity == UART_PARITY_NONE) {
self->char_width = CHAR_WIDTH_9BIT;
} else {
self->char_width = CHAR_WIDTH_8BIT;
}
self->read_buf_head = 0;
self->read_buf_tail = 0;
if (args[7].u_int <= 0) {
// no read buffer
self->read_buf_len = 0;
self->read_buf = NULL;
HAL_NVIC_DisableIRQ(self->irqn);
__HAL_UART_DISABLE_IT(&self->uart, UART_IT_RXNE);
} else {
// read buffer using interrupts
self->read_buf_len = args[7].u_int;
self->read_buf = m_new(byte, args[7].u_int << self->char_width);
__HAL_UART_ENABLE_IT(&self->uart, UART_IT_RXNE);
HAL_NVIC_SetPriority(self->irqn, 0xd, 0xd); // next-to-next-to lowest priority
HAL_NVIC_EnableIRQ(self->irqn);
}
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 busses 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(mp_obj_t type_in, mp_uint_t n_args, mp_uint_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) {
#if defined(PYBV10)
} else if (strcmp(port, "XA") == 0) {
uart_id = PYB_UART_XA;
} else if (strcmp(port, "XB") == 0) {
uart_id = PYB_UART_XB;
} else if (strcmp(port, "YA") == 0) {
uart_id = PYB_UART_YA;
} else if (strcmp(port, "YB") == 0) {
uart_id = PYB_UART_YB;
#endif
} else {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%s) does not exist", port));
}
} else {
uart_id = mp_obj_get_int(args[0]);
if (uart_id < 1 || uart_id > MP_ARRAY_SIZE(pyb_uart_obj_all)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%d) does not exist", uart_id));
}
}
pyb_uart_obj_t *self;
if (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;
pyb_uart_obj_all[uart_id - 1] = self;
} else {
// reference existing UART object
self = 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 self;
}
STATIC mp_obj_t pyb_uart_init(mp_uint_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
return pyb_uart_init_helper(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 = self_in;
self->is_enabled = false;
UART_HandleTypeDef *uart = &self->uart;
HAL_UART_DeInit(uart);
if (uart->Instance == USART1) {
HAL_NVIC_DisableIRQ(USART1_IRQn);
__USART1_FORCE_RESET();
__USART1_RELEASE_RESET();
__USART1_CLK_DISABLE();
} else if (uart->Instance == USART2) {
HAL_NVIC_DisableIRQ(USART2_IRQn);
__USART2_FORCE_RESET();
__USART2_RELEASE_RESET();
__USART2_CLK_DISABLE();
} else if (uart->Instance == USART3) {
HAL_NVIC_DisableIRQ(USART3_IRQn);
__USART3_FORCE_RESET();
__USART3_RELEASE_RESET();
__USART3_CLK_DISABLE();
} else if (uart->Instance == UART4) {
HAL_NVIC_DisableIRQ(UART4_IRQn);
__UART4_FORCE_RESET();
__UART4_RELEASE_RESET();
__UART4_CLK_DISABLE();
} else if (uart->Instance == USART6) {
HAL_NVIC_DisableIRQ(USART6_IRQn);
__USART6_FORCE_RESET();
__USART6_RELEASE_RESET();
__USART6_CLK_DISABLE();
}
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 = self_in;
if (uart_rx_any(self)) {
return mp_const_true;
} else {
return mp_const_false;
}
}
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 = self_in;
// get the character to write (might be 9 bits)
uint16_t data = mp_obj_get_int(char_in);
// write the data
HAL_StatusTypeDef status = HAL_UART_Transmit(&self->uart, (uint8_t*)&data, 1, self->timeout);
if (status != HAL_OK) {
mp_hal_raise(status);
}
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 = 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);
STATIC const mp_map_elem_t pyb_uart_locals_dict_table[] = {
// instance methods
{ MP_OBJ_NEW_QSTR(MP_QSTR_init), (mp_obj_t)&pyb_uart_init_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_deinit), (mp_obj_t)&pyb_uart_deinit_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_any), (mp_obj_t)&pyb_uart_any_obj },
/// \method read([nbytes])
{ MP_OBJ_NEW_QSTR(MP_QSTR_read), (mp_obj_t)&mp_stream_read_obj },
/// \method readall()
{ MP_OBJ_NEW_QSTR(MP_QSTR_readall), (mp_obj_t)&mp_stream_readall_obj },
/// \method readline()
{ MP_OBJ_NEW_QSTR(MP_QSTR_readline), (mp_obj_t)&mp_stream_unbuffered_readline_obj},
/// \method readinto(buf[, nbytes])
{ MP_OBJ_NEW_QSTR(MP_QSTR_readinto), (mp_obj_t)&mp_stream_readinto_obj },
/// \method write(buf)
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&mp_stream_write_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_writechar), (mp_obj_t)&pyb_uart_writechar_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_readchar), (mp_obj_t)&pyb_uart_readchar_obj },
// class constants
{ MP_OBJ_NEW_QSTR(MP_QSTR_RTS), MP_OBJ_NEW_SMALL_INT(UART_HWCONTROL_RTS) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_CTS), MP_OBJ_NEW_SMALL_INT(UART_HWCONTROL_CTS) },
};
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 = self_in;
byte *buf = buf_in;
// check that size is a multiple of character width
if (size & self->char_width) {
*errcode = 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)) {
// we can either return 0 to indicate EOF (then read() method returns b'')
// or return EAGAIN error to indicate non-blocking (then read() method returns None)
return 0;
}
// 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 = self_in;
const byte *buf = buf_in;
// check that size is a multiple of character width
if (size & self->char_width) {
*errcode = EIO;
return MP_STREAM_ERROR;
}
// write the data
HAL_StatusTypeDef status = HAL_UART_Transmit(&self->uart, (uint8_t*)buf, size >> self->char_width, self->timeout);
if (status == HAL_OK) {
// return number of bytes written
return size;
} else {
*errcode = mp_hal_status_to_errno_table[status];
return MP_STREAM_ERROR;
}
}
STATIC mp_uint_t pyb_uart_ioctl(mp_obj_t self_in, mp_uint_t request, int *errcode, ...) {
pyb_uart_obj_t *self = self_in;
va_list vargs;
va_start(vargs, errcode);
mp_uint_t ret;
if (request == MP_IOCTL_POLL) {
mp_uint_t flags = va_arg(vargs, mp_uint_t);
ret = 0;
if ((flags & MP_IOCTL_POLL_RD) && uart_rx_any(self)) {
ret |= MP_IOCTL_POLL_RD;
}
if ((flags & MP_IOCTL_POLL_WR) && __HAL_UART_GET_FLAG(&self->uart, UART_FLAG_TXE)) {
ret |= MP_IOCTL_POLL_WR;
}
} else {
*errcode = EINVAL;
ret = MP_STREAM_ERROR;
}
va_end(vargs);
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,
.iternext = mp_stream_unbuffered_iter,
.stream_p = &uart_stream_p,
.locals_dict = (mp_obj_t)&pyb_uart_locals_dict,
};
Reference in New Issue View Git Blame Copy Permalink