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Merge pull request #6330 from KurtE/rp2040_uart_rs485

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[RP2040] Allow any GPIO pin for RS485 direction pin
This commit is contained in:
Dan Halbert 2022-05-04 13:32:36 -04:00 committed by GitHub
commit b71ea29a8b
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GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 36 additions and 5 deletions
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39
ports/raspberrypi/common-hal/busio/UART.c
View File

@ -112,10 +112,6 @@ void common_hal_busio_uart_construct(busio_uart_obj_t *self,
mp_raise_ValueError(translate("Invalid buffer size"));
}
if ((rs485_dir != NULL) || (rs485_invert)) {
mp_raise_NotImplementedError(translate("RS485 Not yet supported on this device"));
}
uint8_t uart_id = ((((tx != NULL) ? tx->number : rx->number) + 4) / 8) % NUM_UARTS;
if (uart_status[uart_id] != STATUS_FREE) {
@ -126,6 +122,29 @@ void common_hal_busio_uart_construct(busio_uart_obj_t *self,
self->rx_pin = pin_init(uart_id, rx, 1);
self->cts_pin = pin_init(uart_id, cts, 2);
self->rts_pin = pin_init(uart_id, rts, 3);
if (rs485_dir != NULL) {
uint8_t pin = rs485_dir->number;
self->rs485_dir_pin = pin;
self->rs485_invert = rs485_invert;
gpio_init(pin);
claim_pin(rs485_dir);
gpio_disable_pulls(pin);
// Turn on "strong" pin driving (more current available).
hw_write_masked(&padsbank0_hw->io[pin],
PADS_BANK0_GPIO0_DRIVE_VALUE_12MA << PADS_BANK0_GPIO0_DRIVE_LSB,
PADS_BANK0_GPIO0_DRIVE_BITS);
gpio_put(self->rs485_dir_pin, rs485_invert);
gpio_set_dir(self->rs485_dir_pin, GPIO_OUT);
} else {
self->rs485_dir_pin = NO_PIN;
}
uart_status[uart_id] = STATUS_BUSY;
@ -179,10 +198,12 @@ void common_hal_busio_uart_deinit(busio_uart_obj_t *self) {
reset_pin_number(self->rx_pin);
reset_pin_number(self->cts_pin);
reset_pin_number(self->rts_pin);
reset_pin_number(self->rs485_dir_pin);
self->tx_pin = NO_PIN;
self->rx_pin = NO_PIN;
self->cts_pin = NO_PIN;
self->rts_pin = NO_PIN;
self->rs485_dir_pin = NO_PIN;
}
// Write characters.
@ -191,6 +212,11 @@ size_t common_hal_busio_uart_write(busio_uart_obj_t *self, const uint8_t *data,
mp_raise_ValueError(translate("No TX pin"));
}
if (self->rs485_dir_pin != NO_PIN) {
uart_tx_wait_blocking(self->uart);
gpio_put(self->rs485_dir_pin, !self->rs485_invert);
}
size_t left_to_write = len;
while (left_to_write > 0) {
while (uart_is_writable(self->uart) && left_to_write > 0) {
@ -201,7 +227,10 @@ size_t common_hal_busio_uart_write(busio_uart_obj_t *self, const uint8_t *data,
}
RUN_BACKGROUND_TASKS;
}
if (self->rs485_dir_pin != NO_PIN) {
uart_tx_wait_blocking(self->uart);
gpio_put(self->rs485_dir_pin, self->rs485_invert);
}
return len;
}

2
ports/raspberrypi/common-hal/busio/UART.h
View File

@ -37,6 +37,8 @@ typedef struct {
uint8_t tx_pin;
uint8_t rx_pin;
uint8_t cts_pin;
uint8_t rs485_dir_pin;
bool rs485_invert;
uint8_t rts_pin;
uint8_t uart_id;
uint8_t uart_irq_id;