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fix(driver_spi): added bit trans length check for master driver
Closes https://github.com/espressif/esp-idf/issues/16049 Closes https://github.com/espressif/esp-idf/issues/17725
This commit is contained in:
@@ -1,5 +1,5 @@
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/*
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* SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
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* SPDX-FileCopyrightText: 2015-2026 Espressif Systems (Shanghai) CO LTD
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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@@ -1048,6 +1048,8 @@ static SPI_MASTER_ISR_ATTR esp_err_t check_trans_valid(spi_device_handle_t handl
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const spi_bus_attr_t* bus_attr = host->bus_attr;
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bool tx_enabled = (trans_desc->flags & SPI_TRANS_USE_TXDATA) || (trans_desc->tx_buffer);
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bool rx_enabled = (trans_desc->flags & SPI_TRANS_USE_RXDATA) || (trans_desc->rx_buffer);
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uint8_t txlen_extra = trans_desc->length % 8;
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uint8_t rxlen_extra = trans_desc->rxlength % 8;
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spi_transaction_ext_t *t_ext = (spi_transaction_ext_t *)trans_desc;
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bool dummy_enabled = (((trans_desc->flags & SPI_TRANS_VARIABLE_DUMMY) ? t_ext->dummy_bits : handle->cfg.dummy_bits) != 0);
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bool extra_dummy_enabled = handle->hal_dev.timing_conf.timing_dummy;
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@@ -1069,6 +1071,7 @@ static SPI_MASTER_ISR_ATTR esp_err_t check_trans_valid(spi_device_handle_t handl
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SPI_CHECK(!((trans_desc->flags & (SPI_TRANS_MODE_DIO | SPI_TRANS_MODE_QIO)) && !is_half_duplex), "Incompatible when setting to both multi-line mode and half duplex mode", ESP_ERR_INVALID_ARG);
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#ifdef CONFIG_IDF_TARGET_ESP32
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SPI_CHECK(!is_half_duplex || !bus_attr->dma_enabled || !rx_enabled || !tx_enabled, "SPI half duplex mode does not support using DMA with both MOSI and MISO phases.", ESP_ERR_INVALID_ARG);
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SPI_CHECK(!bus_attr->dma_enabled || !rxlen_extra, "rx unaligned byte with DMA is not supported", ESP_ERR_NOT_SUPPORTED);
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#endif
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#if !SOC_SPI_HD_BOTH_INOUT_SUPPORTED
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//On these chips, HW doesn't support using both TX and RX phases when in halfduplex mode
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@@ -1088,6 +1091,8 @@ static SPI_MASTER_ISR_ATTR esp_err_t check_trans_valid(spi_device_handle_t handl
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//Dummy phase is not available when both data out and in are enabled, regardless of FD or HD mode.
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SPI_CHECK(!tx_enabled || !rx_enabled || !dummy_enabled || !extra_dummy_enabled, "Dummy phase is not available when both data out and in are enabled", ESP_ERR_INVALID_ARG);
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SPI_CHECK(!txlen_extra || (txlen_extra >= SPI_LL_TX_MINI_EXTRA_BITS), "tx %d-bit is not supported on this(or this version) chip", ESP_ERR_NOT_SUPPORTED, trans_desc->length);
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SPI_CHECK(!rxlen_extra || (rxlen_extra >= SPI_LL_RX_MINI_EXTRA_BITS), "rx %d-bit is not supported on this chip", ESP_ERR_NOT_SUPPORTED, trans_desc->rxlength);
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if (bus_attr->dma_enabled) {
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SPI_CHECK(trans_desc->length <= SPI_LL_DMA_MAX_BIT_LEN, "txdata transfer > hardware max supported len", ESP_ERR_INVALID_ARG);
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SPI_CHECK(trans_desc->rxlength <= SPI_LL_DMA_MAX_BIT_LEN, "rxdata transfer > hardware max supported len", ESP_ERR_INVALID_ARG);
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@@ -1,5 +1,5 @@
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/*
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* SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
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* SPDX-FileCopyrightText: 2021-2026 Espressif Systems (Shanghai) CO LTD
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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@@ -35,6 +35,19 @@ const static char TAG[] = "test_spi";
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// There is no input-only pin except on esp32 and esp32s2
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#define TEST_SOC_HAS_INPUT_ONLY_PINS (CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2)
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static uint8_t bitswap(uint8_t in)
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{
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uint8_t out = 0;
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for (int i = 0; i < 8; i++) {
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out = out >> 1;
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if (in & 0x80) {
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out |= 0x80;
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}
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in = in << 1;
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}
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return out;
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}
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static void check_spi_pre_n_for(int clk, int pre, int n)
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{
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spi_device_handle_t handle;
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@@ -818,19 +831,6 @@ TEST_CASE("SPI Master DMA test: length, start, not aligned", "[spi]")
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#if (TEST_SPI_PERIPH_NUM >= 2)
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//These will only be enabled on chips with 2 or more SPI peripherals
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static uint8_t bitswap(uint8_t in)
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{
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uint8_t out = 0;
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for (int i = 0; i < 8; i++) {
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out = out >> 1;
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if (in & 0x80) {
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out |= 0x80;
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}
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in = in << 1;
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}
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return out;
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}
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void test_cmd_addr(spi_slave_task_context_t *slave_context, bool lsb_first)
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{
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spi_device_handle_t spi;
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@@ -1758,6 +1758,91 @@ static void test_iram_slave_normal(void)
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TEST_CASE_MULTIPLE_DEVICES("SPI_Master:IRAM_safe", "[spi_ms]", test_master_iram, test_iram_slave_normal);
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#endif
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TEST_CASE("Test master 1-9 bits tx/rx", "[spi]")
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{
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spi_device_handle_t dev0;
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spi_bus_config_t buscfg = SPI_BUS_TEST_DEFAULT_CONFIG();
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buscfg.flags |= SPICOMMON_BUSFLAG_GPIO_PINS;
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spi_device_interface_config_t devcfg = SPI_DEVICE_TEST_DEFAULT_CONFIG();
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spi_transaction_t trans_cfg = {
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.tx_data[0] = 0xc9,
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.tx_data[1] = 0xad,
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.flags = SPI_TRANS_USE_TXDATA | SPI_TRANS_USE_RXDATA,
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};
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uint8_t exp[2], reversed[2] = {bitswap(trans_cfg.tx_data[0]), bitswap(trans_cfg.tx_data[1])};
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for (int dma = 0; dma < 2; dma++) {
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TEST_ESP_OK(spi_bus_initialize(TEST_SPI_HOST, &buscfg, dma ? SPI_DMA_CH_AUTO : SPI_DMA_DISABLED));
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spitest_gpio_output_sel(buscfg.miso_io_num, FUNC_GPIO, spi_periph_signal[TEST_SPI_HOST].spid_out); // set loopback
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for (int cfg = 0; cfg < 2; cfg++) {
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printf("Test %s with DMA: %s\n", cfg ? "LSB" : "MSB", dma ? "AUTO" : "DISABLED");
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devcfg.flags = cfg ? SPI_DEVICE_RXBIT_LSBFIRST : 0;
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TEST_ESP_OK(spi_bus_add_device(TEST_SPI_HOST, &devcfg, &dev0));
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for (int i = 1; i <= 9; i++) {
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trans_cfg.length = i;
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trans_cfg.rxlength = i;
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if (i <= 8) {
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exp[0] = devcfg.flags & SPI_DEVICE_RXBIT_LSBFIRST ? reversed[0] & (0xff >> (8 - i)) : trans_cfg.tx_data[0] & (0xff << (8 - i));
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}
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exp[1] = devcfg.flags & SPI_DEVICE_RXBIT_LSBFIRST ? reversed[1] & (0xff >> (16 - i)) : trans_cfg.tx_data[1] & (0xff << (16 - i));
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#if CONFIG_IDF_TARGET_ESP32
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if ((i % 8) && dma) {
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#else
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if ((i % 8) && ((i % 8 < SPI_LL_TX_MINI_EXTRA_BITS) || (i % 8 < SPI_LL_RX_MINI_EXTRA_BITS))) {
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#endif
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TEST_ESP_ERR(ESP_ERR_NOT_SUPPORTED, spi_device_transmit(dev0, &trans_cfg));
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continue;
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}
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TEST_ESP_OK(spi_device_transmit(dev0, &trans_cfg));
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printf("len %d bits tx %x %x reversed %x %x exp %2x %2x rx %2x %2x\n", i, trans_cfg.tx_data[0], trans_cfg.tx_data[1], reversed[0], reversed[1], exp[0], exp[1], trans_cfg.rx_data[0], trans_cfg.rx_data[1]);
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TEST_ASSERT_EQUAL_HEX8_ARRAY(exp, trans_cfg.rx_data, 2);
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memset(trans_cfg.rx_data, 0, sizeof(trans_cfg.rx_data));
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}
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TEST_ESP_OK(spi_bus_remove_device(dev0));
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printf("--------------------------------\n");
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}
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TEST_ESP_OK(spi_bus_free(TEST_SPI_HOST));
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}
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}
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TEST_CASE("Test master 1-9 bits rx only", "[spi]")
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{
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spi_bus_config_t buscfg = SPI_BUS_TEST_DEFAULT_CONFIG();
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buscfg.flags |= SPICOMMON_BUSFLAG_GPIO_PINS;
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TEST_ESP_OK(spi_bus_initialize(TEST_SPI_HOST, &buscfg, SPI_DMA_DISABLED));
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spi_device_handle_t dev0;
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spi_device_interface_config_t devcfg = SPI_DEVICE_TEST_DEFAULT_CONFIG();
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devcfg.flags |= SPI_DEVICE_HALFDUPLEX;
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TEST_ESP_OK(spi_bus_add_device(TEST_SPI_HOST, &devcfg, &dev0));
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spi_transaction_t trans_cfg = {
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.flags = SPI_TRANS_USE_RXDATA,
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};
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gpio_set_level(buscfg.miso_io_num, 1);
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spitest_gpio_output_sel(buscfg.miso_io_num, FUNC_GPIO, SIG_GPIO_OUT_IDX);
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for (int i = 1; i <= 9; i++) {
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trans_cfg.rxlength = i;
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if ((i % 8) && (i % 8 < SPI_LL_RX_MINI_EXTRA_BITS)) {
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TEST_ESP_ERR(ESP_ERR_NOT_SUPPORTED, spi_device_transmit(dev0, &trans_cfg));
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continue;
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}
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TEST_ESP_OK(spi_device_transmit(dev0, &trans_cfg));
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printf("len %d bits rx %2x %2x\n", i, trans_cfg.rx_data[0], trans_cfg.rx_data[1]);
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if (i <= 8) {
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TEST_ASSERT_EQUAL_HEX8((0xff << (8 - i)), trans_cfg.rx_data[0]);
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}
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TEST_ASSERT_EQUAL_HEX8((0xff << (16 - i)), trans_cfg.rx_data[1]);
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memset(trans_cfg.rx_data, 0, sizeof(trans_cfg.rx_data));
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}
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TEST_ESP_OK(spi_bus_remove_device(dev0));
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TEST_ESP_OK(spi_bus_free(TEST_SPI_HOST));
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}
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#if !CONFIG_IDF_TARGET_ESP32P4 // TODO: IDF-7528, IDF-7529
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TEST_CASE("test_spi_master_sleep_retention", "[spi]")
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{
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@@ -42,6 +42,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 24) //reg len: 24 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 1 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 0 //Default level after bus initialized
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// CS_WORKAROUND: SPI slave with using DMA, the rx dma suffers from unexpected transactions
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@@ -41,6 +41,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 2 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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/**
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@@ -41,6 +41,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 2 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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/**
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@@ -42,6 +42,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 1 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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#define SPI_LL_SUPPORT_CLK_SRC_PRE_DIV 1 //clock source have divider before peripheral
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#define SPI_LL_CLK_SRC_PRE_DIV_MAX 256//div1(8bit)
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@@ -41,6 +41,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 2 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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/**
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@@ -43,6 +43,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 1 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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/**
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@@ -43,6 +43,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS (ESP_CHIP_REV_ABOVE(efuse_hal_chip_revision(), 102) ? 1 : 2) //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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/**
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@@ -40,6 +40,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN SPI_MS_DATA_BITLEN
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 1 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_SUPPORT_CLK_SRC_PRE_DIV 1 //clock source have divider before peripheral
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#define SPI_LL_PERIPH_CLK_DIV_MAX ((SPI_CLKCNT_N + 1) * (SPI_CLKDIV_PRE + 1)) //peripheral internal maxmum clock divider
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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@@ -47,6 +47,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 23) //reg len: 23 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (18 * 32) //Fifo len: 18 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 1 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 8 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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#define SPI_LL_DMA_SHARED 1 //spi_dma shared with adc and dac on S2
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@@ -43,6 +43,8 @@ extern "C" {
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#define SPI_LL_DMA_MAX_BIT_LEN (1 << 18) //reg len: 18 bits
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#define SPI_LL_CPU_MAX_BIT_LEN (16 * 32) //Fifo len: 16 words
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#define SPI_LL_TX_MINI_EXTRA_BITS 2 //Minimum length of TX non byte aligned data in bits
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#define SPI_LL_RX_MINI_EXTRA_BITS 1 //Minimum length of RX non byte aligned data in bits
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#define SPI_LL_MOSI_FREE_LEVEL 1 //Default level after bus initialized
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/**
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@@ -367,6 +367,25 @@ An SPI Host reads and writes data into memory byte by byte. By default, data is
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For example, if ``0b00010`` needs to be sent, it should be written into a ``uint8_t`` variable, and the length for reading should be set to 5 bits. The Device will still receive 8 bits with 3 additional "random" bits, so the reading must be performed correctly.
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Not all chips support data transmission with any bit lengths. Sending or receiving unsupported bit lengths will return :c:macro:`ESP_ERR_NOT_SUPPORTED` error. The supported lengths are shown in the table below (**YES** means support any bits length, **NO** means bytes (8 bits) only):
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+------+--------+-------+----------+--------------------+---------------------+
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| | ESP32 | ESP32-S2 | ESP32-S3/C2/C3/C6 | ESP32-H2/P4/C5/C61 |
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+======+========+=======+==========+====================+=====================+
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| TX | DMA | YES | YES | (bit_len % 8) != 1 | YES |
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+ +--------+-------+----------+--------------------+---------------------+
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| | NO DMA | YES | YES | (bit_len % 8) != 1 | YES |
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+------+--------+-------+----------+--------------------+---------------------+
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| RX | DMA | NO | NO | YES | YES |
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+ +--------+-------+----------+--------------------+---------------------+
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| | NO DMA | YES | NO | YES | YES |
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+------+--------+-------+----------+--------------------+---------------------+
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If you still need to use unsupported bit lengths, you can use the following alternatives:
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1. Use :cpp:member:`spi_transaction_t::cmd` and :cpp:member:`spi_transaction_t::addr` and data phase combination. The drawback is that the command and address phases do not receive data from the slave device.
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2. Use two supported length transmissions combination, like ``2+7`` to implement ``9 bit`` transmission, while keeping the CS line valid. The drawback is that there is a minimum time interval between two transmissions (see :ref:`transaction_time_cost`), and the overall transfer rate is lower.
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On top of that, {IDF_TARGET_NAME} is a little-endian chip, which means that the least significant byte of ``uint16_t`` and ``uint32_t`` variables is stored at the smallest address. Hence, if ``uint16_t`` is stored in memory, bits [7:0] are sent first, followed by bits [15:8].
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For cases when the data to be transmitted has a size differing from ``uint8_t`` arrays, the following macros can be used to transform data to the format that can be sent by the SPI driver directly:
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@@ -528,6 +547,7 @@ There are three factors limiting the transfer speed:
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The main parameter that determines the transfer speed for large transactions is clock frequency. For multiple small transactions, the transfer speed is mostly determined by the length of transaction intervals.
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.. _transaction_time_cost:
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Transaction Duration
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^^^^^^^^^^^^^^^^^^^^
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@@ -367,6 +367,25 @@ SPI 主机逐字节地将数据读入和写入内存。默认情况下,数据
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例如,如果需要发送 ``0b00010``,则应将其写成 ``uint8_t`` 变量,读取长度设置为 5 位。此时,设备仍然会收到 8 位数据,并另有 3 个“随机”位,所以读取过程必须准确。
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不是所有芯片都支持任意位长度的数据传输,发送或接收不支持的位长度时会返回 :c:macro:`ESP_ERR_NOT_SUPPORTED` 错误。支持的长度如下表所示(**YES** 表示支持任意长度,**NO** 表示只支持整字节 8 bits 长度):
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+------+--------+-------+----------+--------------------+---------------------+
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| | ESP32 | ESP32-S2 | ESP32-S3/C2/C3/C6 | ESP32-H2/P4/C5/C61 |
|
||||
+======+========+=======+==========+====================+=====================+
|
||||
| TX | DMA | YES | YES | (bit_len % 8) != 1 | YES |
|
||||
+ +--------+-------+----------+--------------------+---------------------+
|
||||
| | NO DMA | YES | YES | (bit_len % 8) != 1 | YES |
|
||||
+------+--------+-------+----------+--------------------+---------------------+
|
||||
| RX | DMA | NO | NO | YES | YES |
|
||||
+ +--------+-------+----------+--------------------+---------------------+
|
||||
| | NO DMA | YES | NO | YES | YES |
|
||||
+------+--------+-------+----------+--------------------+---------------------+
|
||||
|
||||
如仍需使用不支持的长度传输,根据表格可以有以下替代方法:
|
||||
|
||||
1. 使用 :cpp:member:`spi_transaction_t::cmd` 和 :cpp:member:`spi_transaction_t::addr` 和数据阶段组合。缺点:命令和地址阶段不接收从机数据。
|
||||
2. 使用两次支持长度的传输组合,比如 ``2+7`` 实现 ``9 bit`` 传输,期间保持 CS 线有效。缺点:两次传输之间有最小时间间隔(见 :ref:`transaction_time_cost`),整体速率较低。
|
||||
|
||||
此外,{IDF_TARGET_NAME} 属于小端芯片,即 ``uint16_t`` 和 ``uint32_t`` 变量的最低有效位存储在最小的地址。因此,如果 ``uint16_t`` 存储在内存中,则首先发送位 [7:0],其次是位 [15:8]。
|
||||
|
||||
在某些情况下,要传输的数据大小与 ``uint8_t`` 数组不同,可使用以下宏将数据转换为可由 SPI 驱动直接发送的格式:
|
||||
@@ -528,6 +547,7 @@ GPIO 矩阵与 IO_MUX 管脚
|
||||
|
||||
影响大传输事务传输速度的主要参数是时钟频率。而多个小传输事务的传输速度主要由传输事务间隔时长决定。
|
||||
|
||||
.. _transaction_time_cost:
|
||||
|
||||
传输事务持续时间
|
||||
^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
Reference in New Issue
Block a user