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circuitpython/stmhal/uart.c

1044 lines
36 KiB

/*
* 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 "py/nlr.h"
#include "py/runtime.h"
#include "py/stream.h"
#include "py/mperrno.h"
#include "py/mphal.h"
#include "uart.h"
#include "irq.h"
#include "genhdr/pins.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
#define CHAR_WIDTH_8BIT (0)
#define CHAR_WIDTH_9BIT (1)
struct _pyb_uart_obj_t {
mp_obj_base_t base;
UART_HandleTypeDef uart; // this is 17 words big
IRQn_Type irqn;
pyb_uart_t uart_id : 8;
bool is_enabled : 1;
byte char_width; // 0 for 7,8 bit chars, 1 for 9 bit chars
uint16_t char_mask; // 0x7f for 7 bit, 0xff for 8 bit, 0x1ff for 9 bit
uint16_t timeout; // timeout waiting for first char
uint16_t timeout_char; // timeout waiting between 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
};
STATIC mp_obj_t pyb_uart_deinit(mp_obj_t self_in);
void uart_init0(void) {
for (int i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_uart_obj_all)); i++) {
MP_STATE_PORT(pyb_uart_obj_all)[i] = NULL;
}
}
// unregister all interrupt sources
void uart_deinit(void) {
for (int i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_uart_obj_all)); i++) {
pyb_uart_obj_t *uart_obj = MP_STATE_PORT(pyb_uart_obj_all)[i];
if (uart_obj != NULL) {
pyb_uart_deinit(uart_obj);
}
}
}
STATIC bool uart_exists(int uart_id) {
if (uart_id > MP_ARRAY_SIZE(MP_STATE_PORT(pyb_uart_obj_all))) {
// safeguard against pyb_uart_obj_all array being configured too small
return false;
}
switch (uart_id) {
#if defined(MICROPY_HW_UART1_TX) && defined(MICROPY_HW_UART1_RX)
case PYB_UART_1: return true;
#endif
#if defined(MICROPY_HW_UART2_TX) && defined(MICROPY_HW_UART2_RX)
case PYB_UART_2: return true;
#endif
#if defined(MICROPY_HW_UART3_TX) && defined(MICROPY_HW_UART3_RX)
case PYB_UART_3: return true;
#endif
#if defined(MICROPY_HW_UART4_TX) && defined(MICROPY_HW_UART4_RX)
case PYB_UART_4: return true;
#endif
#if defined(MICROPY_HW_UART5_TX) && defined(MICROPY_HW_UART5_RX)
case PYB_UART_5: return true;
#endif
#if defined(MICROPY_HW_UART6_TX) && defined(MICROPY_HW_UART6_RX)
case PYB_UART_6: return true;
#endif
#if defined(MICROPY_HW_UART7_TX) && defined(MICROPY_HW_UART7_RX)
case PYB_UART_7: return true;
#endif
#if defined(MICROPY_HW_UART8_TX) && defined(MICROPY_HW_UART8_RX)
case PYB_UART_8: return true;
#endif
default: return false;
}
}
// assumes Init parameters have been set up correctly
STATIC bool uart_init2(pyb_uart_obj_t *uart_obj) {
USART_TypeDef *UARTx;
IRQn_Type irqn;
int uart_unit;
const pin_obj_t *pins[4] = {0};
switch (uart_obj->uart_id) {
#if defined(MICROPY_HW_UART1_TX) && defined(MICROPY_HW_UART1_RX)
case PYB_UART_1:
uart_unit = 1;
UARTx = USART1;
irqn = USART1_IRQn;
pins[0] = &MICROPY_HW_UART1_TX;
pins[1] = &MICROPY_HW_UART1_RX;
__USART1_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART2_TX) && defined(MICROPY_HW_UART2_RX)
case PYB_UART_2:
uart_unit = 2;
UARTx = USART2;
irqn = USART2_IRQn;
pins[0] = &MICROPY_HW_UART2_TX;
pins[1] = &MICROPY_HW_UART2_RX;
#if defined(MICROPY_HW_UART2_RTS)
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_RTS) {
pins[2] = &MICROPY_HW_UART2_RTS;
}
#endif
#if defined(MICROPY_HW_UART2_CTS)
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS) {
pins[3] = &MICROPY_HW_UART2_CTS;
}
#endif
__USART2_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART3_TX) && defined(MICROPY_HW_UART3_RX)
case PYB_UART_3:
uart_unit = 3;
UARTx = USART3;
irqn = USART3_IRQn;
pins[0] = &MICROPY_HW_UART3_TX;
pins[1] = &MICROPY_HW_UART3_RX;
#if defined(MICROPY_HW_UART3_RTS)
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_RTS) {
pins[2] = &MICROPY_HW_UART3_RTS;
}
#endif
#if defined(MICROPY_HW_UART3_CTS)
if (uart_obj->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS) {
pins[3] = &MICROPY_HW_UART3_CTS;
}
#endif
__USART3_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART4_TX) && defined(MICROPY_HW_UART4_RX)
case PYB_UART_4:
uart_unit = 4;
UARTx = UART4;
irqn = UART4_IRQn;
pins[0] = &MICROPY_HW_UART4_TX;
pins[1] = &MICROPY_HW_UART4_RX;
__UART4_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART5_TX) && defined(MICROPY_HW_UART5_RX)
case PYB_UART_5:
uart_unit = 5;
UARTx = UART5;
irqn = UART5_IRQn;
pins[0] = &MICROPY_HW_UART5_TX;
pins[1] = &MICROPY_HW_UART5_RX;
__UART5_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART6_TX) && defined(MICROPY_HW_UART6_RX)
case PYB_UART_6:
uart_unit = 6;
UARTx = USART6;
irqn = USART6_IRQn;
pins[0] = &MICROPY_HW_UART6_TX;
pins[1] = &MICROPY_HW_UART6_RX;
__USART6_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART7_TX) && defined(MICROPY_HW_UART7_RX)
case PYB_UART_7:
uart_unit = 7;
UARTx = UART7;
irqn = UART7_IRQn;
pins[0] = &MICROPY_HW_UART7_TX;
pins[1] = &MICROPY_HW_UART7_RX;
__UART7_CLK_ENABLE();
break;
#endif
#if defined(MICROPY_HW_UART8_TX) && defined(MICROPY_HW_UART8_RX)
case PYB_UART_8:
uart_unit = 8;
UARTx = UART8;
irqn = UART8_IRQn;
pins[0] = &MICROPY_HW_UART8_TX;
pins[1] = &MICROPY_HW_UART8_RX;
__UART8_CLK_ENABLE();
break;
#endif
default:
// UART does not exist or is not configured for this board
return false;
}
uint32_t mode = MP_HAL_PIN_MODE_ALT;
uint32_t pull = MP_HAL_PIN_PULL_UP;
for (uint i = 0; i < 4; i++) {
if (pins[i] != NULL) {
bool ret = mp_hal_pin_config_alt(pins[i], mode, pull, AF_FN_UART, uart_unit);
if (!ret) {
return false;
}
}
}
uart_obj->irqn = irqn;
uart_obj->uart.Instance = UARTx;
// 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);
}
*/
mp_uint_t uart_rx_any(pyb_uart_obj_t *self) {
int buffer_bytes = self->read_buf_head - self->read_buf_tail;
if (buffer_bytes < 0) {
return buffer_bytes + self->read_buf_len;
} else if (buffer_bytes > 0) {
return buffer_bytes;
} else {
return __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
}
MICROPY_EVENT_POLL_HOOK
}
}
// 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;
if (__HAL_UART_GET_FLAG(&self->uart, UART_FLAG_RXNE) != RESET) {
// UART was stalled by flow ctrl: re-enable IRQ now we have room in buffer
__HAL_UART_ENABLE_IT(&self->uart, UART_IT_RXNE);
}
return data;
} else {
// no buffering
#if defined(MCU_SERIES_F7) || defined(MCU_SERIES_L4)
return self->uart.Instance->RDR & self->char_mask;
#else
return self->uart.Instance->DR & self->char_mask;
#endif
}
}
// Waits at most timeout milliseconds for TX register to become empty.
// Returns true if can write, false if can't.
STATIC bool uart_tx_wait(pyb_uart_obj_t *self, uint32_t timeout) {
uint32_t start = HAL_GetTick();
for (;;) {
if (__HAL_UART_GET_FLAG(&self->uart, UART_FLAG_TXE)) {
return true; // tx register is empty
}
if (HAL_GetTick() - start >= timeout) {
return false; // timeout
}
MICROPY_EVENT_POLL_HOOK
}
}
// Waits at most timeout milliseconds for UART flag to be set.
// Returns true if flag is/was set, false on timeout.
STATIC bool uart_wait_flag_set(pyb_uart_obj_t *self, uint32_t flag, uint32_t timeout) {
// Note: we don't use WFI to idle in this loop because UART tx doesn't generate
// an interrupt and the flag can be set quickly if the baudrate is large.
uint32_t start = HAL_GetTick();
for (;;) {
if (__HAL_UART_GET_FLAG(&self->uart, flag)) {
return true;
}
if (timeout == 0 || HAL_GetTick() - start >= timeout) {
return false; // timeout
}
}
}
// src - a pointer to the data to send (16-bit aligned for 9-bit chars)
// num_chars - number of characters to send (9-bit chars count for 2 bytes from src)
// *errcode - returns 0 for success, MP_Exxx on error
// returns the number of characters sent (valid even if there was an error)
STATIC size_t uart_tx_data(pyb_uart_obj_t *self, const void *src_in, size_t num_chars, int *errcode) {
if (num_chars == 0) {
*errcode = 0;
return 0;
}
uint32_t timeout;
if (self->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS) {
// CTS can hold off transmission for an arbitrarily long time. Apply
// the overall timeout rather than the character timeout.
timeout = self->timeout;
} else {
// The timeout specified here is for waiting for the TX data register to
// become empty (ie between chars), as well as for the final char to be
// completely transferred. The default value for timeout_char is long
// enough for 1 char, but we need to double it to wait for the last char
// to be transferred to the data register, and then to be transmitted.
timeout = 2 * self->timeout_char;
}
const uint8_t *src = (const uint8_t*)src_in;
size_t num_tx = 0;
USART_TypeDef *uart = self->uart.Instance;
while (num_tx < num_chars) {
if (!uart_wait_flag_set(self, UART_FLAG_TXE, timeout)) {
*errcode = MP_ETIMEDOUT;
return num_tx;
}
uint32_t data;
if (self->char_width == CHAR_WIDTH_9BIT) {
data = *((uint16_t*)src) & 0x1ff;
src += 2;
} else {
data = *src++;
}
#if defined(MCU_SERIES_F4)
uart->DR = data;
#else
uart->TDR = data;
#endif
++num_tx;
}
// wait for the UART frame to complete
if (!uart_wait_flag_set(self, UART_FLAG_TC, timeout)) {
*errcode = MP_ETIMEDOUT;
return num_tx;
}
*errcode = 0;
return num_tx;
}
STATIC void uart_tx_char(pyb_uart_obj_t *uart_obj, int c) {
uint16_t ch = c;
int errcode;
uart_tx_data(uart_obj, &ch, 1, &errcode);
}
void uart_tx_strn(pyb_uart_obj_t *uart_obj, const char *str, uint len) {
int errcode;
uart_tx_data(uart_obj, str, len, &errcode);
}
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 = MP_STATE_PORT(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) {
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 read data if room in buf
#if defined(MCU_SERIES_F7) || defined(MCU_SERIES_L4)
int data = self->uart.Instance->RDR; // clears UART_FLAG_RXNE
#else
int data = self->uart.Instance->DR; // clears UART_FLAG_RXNE
#endif
data &= self->char_mask;
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 { // No room: leave char in buf, disable interrupt
__HAL_UART_DISABLE_IT(&self->uart, UART_IT_RXNE);
}
}
}
}
/******************************************************************************/
/* Micro Python bindings */
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 = self_in;
if (!self->is_enabled) {
mp_printf(print, "UART(%u)", self->uart_id);
} else {
mp_int_t bits = (self->uart.Init.WordLength == UART_WORDLENGTH_8B ? 8 : 9);
if (self->uart.Init.Parity != UART_PARITY_NONE) {
bits -= 1;
}
mp_printf(print, "UART(%u, baudrate=%u, bits=%u, parity=",
self->uart_id, self->uart.Init.BaudRate, bits);
if (self->uart.Init.Parity == UART_PARITY_NONE) {
mp_print_str(print, "None");
} else {
mp_printf(print, "%u", self->uart.Init.Parity == UART_PARITY_EVEN ? 0 : 1);
}
if (self->uart.Init.HwFlowCtl) {
mp_printf(print, ", flow=");
if (self->uart.Init.HwFlowCtl & UART_HWCONTROL_RTS) {
mp_printf(print, "RTS%s", self->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS ? "|" : "");
}
if (self->uart.Init.HwFlowCtl & UART_HWCONTROL_CTS) {
mp_printf(print, "CTS");
}
}
mp_printf(print, ", 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 == 0 ? 0 : self->read_buf_len - 1); // -1 to adjust for usable length of buffer
}
}
/// \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, 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
struct {
mp_arg_val_t baudrate, bits, parity, stop, flow, timeout, timeout_char, 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);
// set the UART configuration values
memset(&self->uart, 0, sizeof(self->uart));
UART_InitTypeDef *init = &self->uart.Init;
// baudrate
init->BaudRate = args.baudrate.u_int;
// parity
mp_int_t bits = args.bits.u_int;
if (args.parity.u_obj == mp_const_none) {
init->Parity = UART_PARITY_NONE;
} else {
mp_int_t parity = mp_obj_get_int(args.parity.u_obj);
init->Parity = (parity & 1) ? UART_PARITY_ODD : UART_PARITY_EVEN;
bits += 1; // STs convention has bits including parity
}
// number of bits
if (bits == 8) {
init->WordLength = UART_WORDLENGTH_8B;
} else if (bits == 9) {
init->WordLength = UART_WORDLENGTH_9B;
} else {
mp_raise_ValueError("unsupported combination of bits and parity");
}
// stop bits
switch (args.stop.u_int) {
case 1: init->StopBits = UART_STOPBITS_1; break;
default: init->StopBits = UART_STOPBITS_2; break;
}
// flow control
init->HwFlowCtl = args.flow.u_int;
// extra config (not yet configurable)
init->Mode = UART_MODE_TX_RX;
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) doesn't exist", self->uart_id));
}
// 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 / init->BaudRate + 2;
if (self->timeout_char < min_timeout_char) {
self->timeout_char = min_timeout_char;
}
// 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_mask = 0x1ff;
self->char_width = CHAR_WIDTH_9BIT;
} else {
if (init->WordLength == UART_WORDLENGTH_9B || init->Parity == UART_PARITY_NONE) {
self->char_mask = 0xff;
} else {
self->char_mask = 0x7f;
}
self->char_width = CHAR_WIDTH_8BIT;
}
self->read_buf_head = 0;
self->read_buf_tail = 0;
if (args.read_buf_len.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.read_buf_len.u_int + 1; // +1 to adjust for usable length of buffer
self->read_buf = m_new(byte, self->read_buf_len << self->char_width);
__HAL_UART_ENABLE_IT(&self->uart, UART_IT_RXNE);
HAL_NVIC_SetPriority(self->irqn, IRQ_PRI_UART, IRQ_SUBPRI_UART);
HAL_NVIC_EnableIRQ(self->irqn);
}
// compute actual baudrate that was configured
// (this formula assumes UART_OVERSAMPLING_16)
uint32_t actual_baudrate = 0;
#if defined(MCU_SERIES_F7)
UART_ClockSourceTypeDef clocksource = UART_CLOCKSOURCE_UNDEFINED;
UART_GETCLOCKSOURCE(&self->uart, clocksource);
switch (clocksource) {
case UART_CLOCKSOURCE_PCLK1: actual_baudrate = HAL_RCC_GetPCLK1Freq(); break;
case UART_CLOCKSOURCE_PCLK2: actual_baudrate = HAL_RCC_GetPCLK2Freq(); break;
case UART_CLOCKSOURCE_HSI: actual_baudrate = HSI_VALUE; break;
case UART_CLOCKSOURCE_SYSCLK: actual_baudrate = HAL_RCC_GetSysClockFreq(); break;
case UART_CLOCKSOURCE_LSE: actual_baudrate = LSE_VALUE; break;
case UART_CLOCKSOURCE_UNDEFINED: break;
}
#else
if (self->uart.Instance == USART1
#if defined(USART6)
|| self->uart.Instance == USART6
#endif
) {
actual_baudrate = HAL_RCC_GetPCLK2Freq();
} else {
actual_baudrate = HAL_RCC_GetPCLK1Freq();
}
#endif
actual_baudrate /= self->uart.Instance->BRR;
// check we could set the baudrate within 5%
uint32_t baudrate_diff;
if (actual_baudrate > init->BaudRate) {
baudrate_diff = actual_baudrate - init->BaudRate;
} else {
baudrate_diff = init->BaudRate - actual_baudrate;
}
init->BaudRate = actual_baudrate; // remember actual baudrate for printing
if (20 * baudrate_diff > init->BaudRate) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "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 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(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
} else {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%s) doesn't exist", port));
}
} else {
uart_id = mp_obj_get_int(args[0]);
if (!uart_exists(uart_id)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%d) doesn't exist", 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 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();
#if defined(USART3)
} else if (uart->Instance == USART3) {
HAL_NVIC_DisableIRQ(USART3_IRQn);
__USART3_FORCE_RESET();
__USART3_RELEASE_RESET();
__USART3_CLK_DISABLE();
#endif
#if defined(UART4)
} else if (uart->Instance == UART4) {
HAL_NVIC_DisableIRQ(UART4_IRQn);
__UART4_FORCE_RESET();
__UART4_RELEASE_RESET();
__UART4_CLK_DISABLE();
#endif
#if defined(UART5)
} else if (uart->Instance == UART5) {
HAL_NVIC_DisableIRQ(UART5_IRQn);
__UART5_FORCE_RESET();
__UART5_RELEASE_RESET();
__UART5_CLK_DISABLE();
#endif
#if defined(UART6)
} else if (uart->Instance == USART6) {
HAL_NVIC_DisableIRQ(USART6_IRQn);
__USART6_FORCE_RESET();
__USART6_RELEASE_RESET();
__USART6_CLK_DISABLE();
#endif
#if defined(UART7)
} else if (uart->Instance == UART7) {
HAL_NVIC_DisableIRQ(UART7_IRQn);
__UART7_FORCE_RESET();
__UART7_RELEASE_RESET();
__UART7_CLK_DISABLE();
#endif
#if defined(UART8)
} else if (uart->Instance == UART8) {
HAL_NVIC_DisableIRQ(UART8_IRQn);
__UART8_FORCE_RESET();
__UART8_RELEASE_RESET();
__UART8_CLK_DISABLE();
#endif
}
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;
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 = 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 = 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 = self_in;
#if defined(MCU_SERIES_F7) || defined(MCU_SERIES_L4)
self->uart.Instance->RQR = USART_RQR_SBKRQ; // write-only register
#else
self->uart.Instance->CR1 |= USART_CR1_SBK;
#endif
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_sendbreak_obj, pyb_uart_sendbreak);
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_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) },
// 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) },
};
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 = 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 = 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, mp_uint_t arg, int *errcode) {
pyb_uart_obj_t *self = self_in;
mp_uint_t ret;
if (request == MP_STREAM_POLL) {
mp_uint_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) && __HAL_UART_GET_FLAG(&self->uart, UART_FLAG_TXE)) {
ret |= MP_STREAM_POLL_WR;
}
} 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,
};