Hello Community!
I am struggling with assigning numbers to I2C buses in my BPi, doing the same(?) thing in two different ways i am getting two different results.
By default, there is only /dev/i2c-0 node available, AFAIK because HDMI uses this bus.
1. Using build-in overlay for i2c0 bus (overlays=i2c0 in /boot/armbianEnv.txt) enables another i2c bus. In this case, /dev/i2c-0 is the bus connected to pins 3 and 5 at 40-pin header. The other bus (enabled by default) becomes /dev/i2c-1. It doesn't matter how many times i reset my board, assignment doesn't change.
2. The second way is to create my own overlay by cloning this code and compiling it with armbian-add-ovelray command. It also enables another i2c bus. However, in this case the buses are swapped, /dev/i2c-0 doesn't change, the newly created bus is /dev/i2c-1 and works fine with sensors connected to pins 3 and 5. This enumeration also doesn't change after reboot.
Can someone tell me why does it happens? Does the cod for build-in overlay differ from the shared one?
Please, be patient for newbie user
Here is the version:
cat /etc/armbian-release
# PLEASE DO NOT EDIT THIS FILE
BOARD=bananapim2zero
BOARD_NAME="Banana Pi M2 Zero"
BOARDFAMILY=sun8i
BUILD_REPOSITORY_URL=https://github.com/armbian/build
BUILD_REPOSITORY_COMMIT=7184c5aa8
LINUXFAMILY=sunxi
ARCH=arm
BOOT_SOC=
IMAGE_TYPE=stable
BOARD_TYPE=csc
INITRD_ARCH=arm
KERNEL_IMAGE_TYPE=zImage
KERNEL_TARGET=legacy,current,edge
KERNEL_TEST_TARGET=current
FORCE_BOOTSCRIPT_UPDATE=
FORCE_UBOOT_UPDATE=
OVERLAY_DIR="/boot/dtb/allwinner/overlay"
VENDOR="Armbian"
VENDORDOCS="https://docs.armbian.com"
VENDORURL="https://www.armbian.com/"
VENDORSUPPORT="https://forum.armbian.com"
VENDORBUGS="https://www.armbian.com/bugs"
BOOTSCRIPT_FORCE_UPDATE="no"
BOOTSCRIPT_DST="boot.cmd"
VERSION=25.2.2
REVISION=25.2.2
BRANCH=current
