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led_ws2812b: use open drain data signal

This commit is contained in:
King Kévin 2020-03-09 09:44:29 +01:00
parent 9b9751e79d
commit e9f7e574ba
1 changed files with 4 additions and 1 deletions
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5
lib/led_ws2812b.c
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@ -38,6 +38,9 @@
/** @defgroup led_ws2812b_spi SPI peripheral used to control the WS2812B LEDs
* @{
*/
/** SPI peripheral
* @note SPI2 is 5V tolerant and can be operated in open-drain mode will 1 kO pull-up resistor to 5V to get 5V signal level
*/
#define LED_WS2812B_SPI 2 /**< SPI peripheral */
/** @} */
@ -105,7 +108,7 @@ void led_ws2812b_setup(void)
// setup SPI to transmit data
rcc_periph_clock_enable(RCC_SPI_MOSI_PORT(LED_WS2812B_SPI)); // enable clock for SPI output peripheral
gpio_set_mode(SPI_MOSI_PORT(LED_WS2812B_SPI), GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, SPI_MOSI_PIN(LED_WS2812B_SPI)); // set MISO as output (needs to be shifted to 5V)
gpio_set_mode(SPI_MOSI_PORT(LED_WS2812B_SPI), GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_OPENDRAIN, SPI_MOSI_PIN(LED_WS2812B_SPI)); // set MOSI as output (push-pull needs to be shifted to 5V, open-drain consumes up to 5 mA with pull-up resistor of 1 kO)
rcc_periph_clock_enable(RCC_AFIO); // enable clock for SPI alternate function
rcc_periph_clock_enable(RCC_SPI(LED_WS2812B_SPI)); // enable clock for SPI peripheral
spi_reset(SPI(LED_WS2812B_SPI)); // clear SPI values to default