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esp8266: Allow for MOSI or MISO only SPI. Fixes #65

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This commit is contained in:
Scott Shawcroft 2017-02-19 13:15:23 +01:00
parent 3dda38c8ab
commit b7ded4c934
1 changed files with 27 additions and 2 deletions
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29
esp8266/common-hal/nativeio/SPI.c
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@ -41,11 +41,36 @@ extern const mcu_pin_obj_t pin_MTDI;
void common_hal_nativeio_spi_construct(nativeio_spi_obj_t *self,
const mcu_pin_obj_t * clock, const mcu_pin_obj_t * mosi,
const mcu_pin_obj_t * miso) {
if (clock != &pin_MTMS || mosi != &pin_MTCK || miso != &pin_MTDI) {
if (clock != &pin_MTMS || !((mosi == &pin_MTCK && miso == MP_OBJ_TO_PTR(mp_const_none)) ||
(mosi == MP_OBJ_TO_PTR(mp_const_none) && miso == &pin_MTDI))) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_OSError,
"Pins not valid for SPI"));
}
spi_init(HSPI);
uint32_t clock_div_flag = 0;
if (SPI_CLK_USE_DIV) {
clock_div_flag = 0x0001;
}
// Set bit 9 if 80MHz sysclock required
WRITE_PERI_REG(PERIPHS_IO_MUX, 0x105 | (clock_div_flag<<9));
// GPIO12 is HSPI MISO pin (Master Data In)
if (miso == &pin_MTDI) {
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDI_U, 2);
}
// GPIO13 is HSPI MOSI pin (Master Data Out)
if (mosi == &pin_MTCK) {
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTCK_U, 2);
}
// GPIO14 is HSPI CLK pin (Clock)
PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTMS_U, 2);
spi_clock(HSPI, SPI_CLK_PREDIV, SPI_CLK_CNTDIV);
spi_tx_byte_order(HSPI, SPI_BYTE_ORDER_HIGH_TO_LOW);
spi_rx_byte_order(HSPI, SPI_BYTE_ORDER_HIGH_TO_LOW);
SET_PERI_REG_MASK(SPI_USER(HSPI), SPI_CS_SETUP|SPI_CS_HOLD);
CLEAR_PERI_REG_MASK(SPI_USER(HSPI), SPI_FLASH_MODE);
}
void common_hal_nativeio_spi_deinit(nativeio_spi_obj_t *self) {