RIOT-OS/RIOT
RIOT-OS/RIOT
1
0
Fork 0
mirror of https://github.com/RIOT-OS/RIOT.git synced 2024-12-29 04:50:03 +01:00
Code Releases Activity

cpu/esp32: improve UART initialization

Browse Source 
The TX line is set and temporarily configured as a pull-up open-drain output before configuring it as a push-pull output to avoid a several msec long LOW pulse resulting in some garbage.
This commit is contained in:
Gunar Schorcht 2023-01-14 13:55:03 +01:00
parent fe21e82079
commit 3085b92e8f
1 changed files with 8 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
cpu/esp_common/periph/uart.c
View File

@ -179,11 +179,14 @@ int uart_init(uart_t uart, uint32_t baudrate, uart_rx_cb_t rx_cb, void *arg)
gpio_set_pin_usage(uart_config[uart].rxd, _GPIO); gpio_set_pin_usage(uart_config[uart].rxd, _GPIO);
} }
/* try to initialize the pins as GPIOs first */ /* Try to initialize the pins where the TX line is set and temporarily
if ((uart_config[uart].txd != GPIO_UNDEF && * configured as a pull-up open-drain output before configuring it as
gpio_init(uart_config[uart].txd, GPIO_OUT)) || * a push-pull output to avoid a several msec long LOW pulse resulting
(uart_config[uart].rxd != GPIO_UNDEF && * in some garbage */
gpio_init(uart_config[uart].rxd, GPIO_IN_PU))) { gpio_set(uart_config[uart].txd);
if (gpio_init(uart_config[uart].txd, GPIO_OD_PU) ||
gpio_init(uart_config[uart].txd, GPIO_OUT) ||
gpio_init(uart_config[uart].rxd, GPIO_IN_PU)) {
return -1; return -1;
} }