Some I2C addresses not usable (with developer kit)


I have two (identical) I2C devices connected to I2C bus 1 on a Jetson Xavier AGX developer kit running Jetpack 4.6. The devices have the addresses 65 and 68. The device with address 68 works flawlessly. The device with address 65 cannot be accessed. A fix is to change its address to 69. Then the device works flawlessly as well.

With address 65 I most often get a “Device or Resource is busy” error. Accordingly my Logic Analyzer tells me that no communication on the bus was happening. Sometimes I get a “Remote I/O error”. Then the START sequence has been launched + the first 8 clocks were generated, however SDA is low all the time.
The error is still present when only one device is present on the bus or even when no device is present.

Is there an explanation for this error and does a list of not usable I2C addresses exist, so I can avoid them in the future?

Best regards,

hello tobias.gehring,

you may disassembler the dtb file into text file for examination,
for example, dtc -I dtb -O dts -o output.txt tegra194-p2888-0001-p2822-0000.dtb