docs: clarify 7-pin ST7789 (SDA/SCL) mapping to shared SPI bus in hw_pins.h and README wiring

This commit is contained in:
2026-09-10 06:01:10 +02:00
parent 686b8d1f6f
commit 663fb0643f
2 changed files with 28 additions and 16 deletions

View File

@@ -11,17 +11,20 @@
#include "hal/gpio_types.h"
#include "driver/spi_master.h"
/* Shared SPI2_HOST (VSPI) bus */
/* Shared SPI2_HOST (VSPI) bus.
* NOTE: on 7-pin ST7789 modules, the display labels these SDA (MOSI) and
* SCL (SCK) - they tap the SAME shared bus as the MFRC522. */
#define HW_SPI_HOST (SPI2_HOST)
#define HW_SPI_SCK_GPIO (GPIO_NUM_18)
#define HW_SPI_MOSI_GPIO (GPIO_NUM_23)
#define HW_SPI_MISO_GPIO (GPIO_NUM_19)
#define HW_SPI_SCK_GPIO (GPIO_NUM_18) /* display SCL + MFRC522 SCK */
#define HW_SPI_MOSI_GPIO (GPIO_NUM_23) /* display SDA + MFRC522 MOSI */
#define HW_SPI_MISO_GPIO (GPIO_NUM_19) /* MFRC522 MISO only */
/* MFRC522 RFID reader */
#define HW_RC522_CS_GPIO (GPIO_NUM_5)
#define HW_RC522_RST_GPIO (GPIO_NUM_22)
/* ST7789 display */
/* ST7789 display - 7-pin breakout: CS / DC / RST / SDA / SCL / GND / VCC.
* SDA and SCL share the SPI bus above (SCL=HW_SPI_SCK, SDA=HW_SPI_MOSI). */
#define HW_LCD_CS_GPIO (GPIO_NUM_15)
#define HW_LCD_DC_GPIO (GPIO_NUM_2)
#define HW_LCD_RST_GPIO (GPIO_NUM_4)