From 87623082e331b9fdbac198b287ffac6ac4953bd3 Mon Sep 17 00:00:00 2001 From: Damien George Date: Thu, 6 Dec 2018 15:40:22 +1100 Subject: [PATCH] esp32/machine_uart: Implement UART.sendbreak() method. The uart_write_bytes_with_break() function requires non-zero data to be sent before the break, so a standalone break must be synthesised. --- ports/esp32/machine_uart.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/ports/esp32/machine_uart.c b/ports/esp32/machine_uart.c index 6aeda63164..b3c70de1e7 100644 --- a/ports/esp32/machine_uart.c +++ b/ports/esp32/machine_uart.c @@ -294,6 +294,37 @@ STATIC mp_obj_t machine_uart_any(mp_obj_t self_in) { } STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_any_obj, machine_uart_any); +STATIC mp_obj_t machine_uart_sendbreak(mp_obj_t self_in) { + machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in); + + // Save settings + uart_word_length_t word_length; + uart_parity_t parity; + uart_get_word_length(self->uart_num, &word_length); + uart_get_parity(self->uart_num, &parity); + + // Synthesise the break condition by either a longer word or using even parity + uart_wait_tx_done(self->uart_num, pdMS_TO_TICKS(1000)); + if (word_length != UART_DATA_8_BITS) { + uart_set_word_length(self->uart_num, UART_DATA_8_BITS); + } else if (parity == UART_PARITY_DISABLE) { + uart_set_parity(self->uart_num, UART_PARITY_EVEN); + } else { + // Cannot synthesise break + mp_raise_OSError(MP_EPERM); + } + char buf[1] = {0}; + uart_write_bytes(self->uart_num, buf, 1); + uart_wait_tx_done(self->uart_num, pdMS_TO_TICKS(1000)); + + // Restore original settings + uart_set_word_length(self->uart_num, word_length); + uart_set_parity(self->uart_num, parity); + + return mp_const_none; +} +STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_sendbreak_obj, machine_uart_sendbreak); + 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) }, @@ -302,6 +333,7 @@ STATIC const mp_rom_map_elem_t machine_uart_locals_dict_table[] = { { 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) }, }; STATIC MP_DEFINE_CONST_DICT(machine_uart_locals_dict, machine_uart_locals_dict_table);