diff options
| -rw-r--r-- | stmhal/uart.c | 54 | ||||
| -rw-r--r-- | tests/pyb/uart.py | 7 | ||||
| -rw-r--r-- | tests/pyb/uart.py.exp | 8 |
3 files changed, 61 insertions, 8 deletions
diff --git a/stmhal/uart.c b/stmhal/uart.c index 8b72327c24..d96c22850f 100644 --- a/stmhal/uart.c +++ b/stmhal/uart.c @@ -331,13 +331,37 @@ int uart_rx_char(pyb_uart_obj_t *self) { } } +// 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 + } + __WFI(); + } +} + +STATIC HAL_StatusTypeDef uart_tx_data(pyb_uart_obj_t *self, uint8_t *data, uint16_t len) { + // 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. + return HAL_UART_Transmit(&self->uart, data, len, 2 * self->timeout_char); +} + 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); + uart_tx_data(uart_obj, &ch, 1); } 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); + uart_tx_data(uart_obj, (uint8_t*)str, len); } void uart_tx_strn_cooked(pyb_uart_obj_t *uart_obj, const char *str, uint len) { @@ -480,9 +504,16 @@ STATIC mp_obj_t pyb_uart_init_helper(pyb_uart_obj_t *self, mp_uint_t n_args, con nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "UART(%d) does not exist", self->uart_id)); } - // set timeouts + // set timeout self->timeout = args[5].u_int; + + // set timeout_char + // make sure it is at least as long as a whole character (13 bits to be safe) self->timeout_char = args[6].u_int; + uint32_t min_timeout_char = 13000 / init->BaudRate + 1; + 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); @@ -689,8 +720,13 @@ STATIC mp_obj_t pyb_uart_writechar(mp_obj_t self_in, mp_obj_t char_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); + // write the character + HAL_StatusTypeDef status; + if (uart_tx_wait(self, self->timeout)) { + status = uart_tx_data(self, (uint8_t*)&data, 1); + } else { + status = HAL_TIMEOUT; + } if (status != HAL_OK) { mp_hal_raise(status); @@ -807,8 +843,14 @@ STATIC mp_uint_t pyb_uart_write(mp_obj_t self_in, const void *buf_in, mp_uint_t return MP_STREAM_ERROR; } + // wait to be able to write the first character + if (!uart_tx_wait(self, self->timeout)) { + *errcode = EAGAIN; + return MP_STREAM_ERROR; + } + // write the data - HAL_StatusTypeDef status = HAL_UART_Transmit(&self->uart, (uint8_t*)buf, size >> self->char_width, self->timeout); + HAL_StatusTypeDef status = uart_tx_data(self, (uint8_t*)buf, size >> self->char_width); if (status == HAL_OK) { // return number of bytes written diff --git a/tests/pyb/uart.py b/tests/pyb/uart.py index cb0be91c0b..838dd9cfc6 100644 --- a/tests/pyb/uart.py +++ b/tests/pyb/uart.py @@ -23,3 +23,10 @@ print(uart.writechar(1)) # make sure this method exists uart.sendbreak() + +# non-blocking mode +uart = UART(1, 9600, timeout=0) +print(uart.write(b'1')) +print(uart.write(b'abcd')) +print(uart.writechar(1)) +print(uart.read(100)) diff --git a/tests/pyb/uart.py.exp b/tests/pyb/uart.py.exp index ea300c90cb..4be50d328a 100644 --- a/tests/pyb/uart.py.exp +++ b/tests/pyb/uart.py.exp @@ -12,9 +12,13 @@ UART XB UART YA UART YB ValueError Z -UART(1, baudrate=9600, bits=8, parity=None, stop=1, timeout=1000, timeout_char=0, read_buf_len=64) -UART(1, baudrate=2400, bits=8, parity=None, stop=1, timeout=1000, timeout_char=0, read_buf_len=64) +UART(1, baudrate=9600, bits=8, parity=None, stop=1, timeout=1000, timeout_char=2, read_buf_len=64) +UART(1, baudrate=2400, bits=8, parity=None, stop=1, timeout=1000, timeout_char=6, read_buf_len=64) 0 3 4 None +1 +4 +None +None |