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Change SPI_USE_RXDATA->SPI_TRANS_USE_RXDATA and SPI_USE_TXDATA->SPI_TRANS_USE_TXDATA on documentation

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Closes https://github.com/espressif/esp-idf/pull/2802
This commit is contained in:
Oleg Antonyan 2018-12-07 09:34:15 +02:00 committed by Mahavir Jain
parent 058c6afd3c
commit 4430456b64
2 changed files with 6 additions and 6 deletions
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4
components/driver/include/driver/spi_master.h
View File

@ -133,11 +133,11 @@ struct spi_transaction_t {
void *user; ///< User-defined variable. Can be used to store eg transaction ID.
union {
const void *tx_buffer; ///< Pointer to transmit buffer, or NULL for no MOSI phase
uint8_t tx_data[4]; ///< If SPI_USE_TXDATA is set, data set here is sent directly from this variable.
uint8_t tx_data[4]; ///< If SPI_TRANS_USE_TXDATA is set, data set here is sent directly from this variable.
};
union {
void *rx_buffer; ///< Pointer to receive buffer, or NULL for no MISO phase. Written by 4 bytes-unit if DMA is used.
uint8_t rx_data[4]; ///< If SPI_USE_RXDATA is set, data is received directly to this variable
uint8_t rx_data[4]; ///< If SPI_TRANS_USE_RXDATA is set, data is received directly to this variable
};
} ; //the rx data should start from a 32-bit aligned address to get around dma issue.

8
docs/en/api-reference/peripherals/spi_master.rst
View File

@ -78,8 +78,8 @@ and/or address. This is reflected in the device configuration: when the ``comman
fields are set to zero, no command or address phase is done.
Something similar is true for the read and write phase: not every transaction needs both data to be written
as well as data to be read. When ``rx_buffer`` is NULL (and SPI_USE_RXDATA) is not set) the read phase
is skipped. When ``tx_buffer`` is NULL (and SPI_USE_TXDATA) is not set) the write phase is skipped.
as well as data to be read. When ``rx_buffer`` is NULL (and SPI_TRANS_USE_RXDATA) is not set) the read phase
is skipped. When ``tx_buffer`` is NULL (and SPI_TRANS_USE_TXDATA) is not set) the write phase is skipped.
The driver offers two different kinds of transactions: the interrupt
transactions and the polling transactions. Each device can choose one kind of
@ -205,8 +205,8 @@ Tips
1. Transactions with small amount of data:
Sometimes, the amount of data is very small making it less than optimal allocating a separate buffer
for it. If the data to be transferred is 32 bits or less, it can be stored in the transaction struct
itself. For transmitted data, use the ``tx_data`` member for this and set the ``SPI_USE_TXDATA`` flag
on the transmission. For received data, use ``rx_data`` and set ``SPI_USE_RXDATA``. In both cases, do
itself. For transmitted data, use the ``tx_data`` member for this and set the ``SPI_TRANS_USE_TXDATA`` flag
on the transmission. For received data, use ``rx_data`` and set ``SPI_TRANS_USE_RXDATA``. In both cases, do
not touch the ``tx_buffer`` or ``rx_buffer`` members, because they use the same memory locations
as ``tx_data`` and ``rx_data``.