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add support for half-duplex SPI on STM parts

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This commit is contained in:
Scott Gauche 2022-02-07 21:08:44 -05:00
parent 5afd7d420d
commit 4110b44b8a
1 changed files with 10 additions and 7 deletions
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17
ports/stm/common-hal/busio/SPI.c
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@ -208,8 +208,13 @@ void common_hal_busio_spi_construct(busio_spi_obj_t *self,
self->handle.Instance = SPIx;
self->handle.Init.Mode = SPI_MODE_MASTER;
// Direction change only required for RX-only, see RefMan RM0090:884
self->handle.Init.Direction = (self->mosi == NULL) ? SPI_DIRECTION_2LINES_RXONLY : SPI_DIRECTION_2LINES;
if (self->mosi == NULL && self->miso != NULL) {
self->handle.Init.Direction = SPI_DIRECTION_2LINES_RXONLY;
} else if (self->mosi != NULL && self->miso == NULL) {
self->handle.Init.Direction = SPI_DIRECTION_1LINE;
} else if (self->mosi != NULL && self->miso != NULL) {
self->handle.Init.Direction = SPI_DIRECTION_2LINES;
}
self->handle.Init.DataSize = SPI_DATASIZE_8BIT;
self->handle.Init.CLKPolarity = SPI_POLARITY_LOW;
self->handle.Init.CLKPhase = SPI_PHASE_1EDGE;
@ -340,13 +345,11 @@ bool common_hal_busio_spi_write(busio_spi_obj_t *self,
bool common_hal_busio_spi_read(busio_spi_obj_t *self,
uint8_t *data, size_t len, uint8_t write_value) {
if (self->miso == NULL) {
mp_raise_ValueError(translate("No MISO Pin"));
}
HAL_StatusTypeDef result = HAL_OK;
if (self->mosi == NULL) {
// If in modes SPI_DIRECTION_2LINES_RXONLY or SPI_DIRECTION_1LINE
if ((self->mosi == NULL && self->miso != NULL) || (self->mosi != NULL && self->miso == NULL)) {
result = HAL_SPI_Receive(&self->handle, data, (uint16_t)len, HAL_MAX_DELAY);
} else {
} else { // Else SPI_DIRECTION_2LINES
memset(data, write_value, len);
result = HAL_SPI_TransmitReceive(&self->handle, data, data, (uint16_t)len, HAL_MAX_DELAY);
}