PCF8574 I2C configuration for 14.0-CURRENT on a RPi2B
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Date: Sun, 06 Mar 2022 18:11:50 UTC
Greetings, My RPi2B GPIO header connects to a PCF8574 I2C adapter with these pins: RPi2B PCF8574 --------------- ------- Pin 2 - +5VDC <-> VCC Pin 3 - GPIO 2 <-> SDA Pin 5 - GPIO 3 <-> SCL Pin 39 - Gnd <-> GND /boot/loader.conf contains these lines: root@generic:/boot # cat /boot/loader.conf # Configure USB OTG; see usb_template(4). hw.usb.template=3 umodem_load="YES" # Disable the beastie menu and color beastie_disable="YES" loader_color="NO" gpioiic_load="YES" and /boot/msdos/config.txt looks like this: root@generic:/boot # cat /boot/msdos/config.txt init_uart_clock=3000000 enable_uart=1 kernel=u-boot.bin kernel7=u-boot.bin dtoverlay=mmc / { gpioiic0 { compatible = "i2c-gpio"; pinctrl-names = "default"; pinctrl-0 = <&pinctrl_gpioiic0>; scl-gpios = <&gpio2 3 GPIO_ACTIVE_HIGH>; sda-gpios = <&gpio3 5 GPIO_ACTIVE_HIGH>; status = "okay"; }; }; Nothing happens: root@generic:/boot # i2c -sv dev: /dev/iic0, addr: 0x0, r/w: r, offset: 0x00, width: 8, count: 1 Error opening I2C controller (/dev/iic0): No such file or directory What's missing? Thank you in advance. Danke, -- Don, KB7RPU, https://www.qsl.net/kb7rpu There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.