linux - Set Up I2C Address Without Device Attached -


i've been trying learn i2c today, it's taken me time set i've got raspberry pi configured i2c-tools installed , can see /dev/i2c-0.

however when run i2cdetect -y 0 empty address table. makes sense don't have device connected i2c bus. able write i2c pins , observe output using oscilloscope or connect led can see state changes.

is possible, , if how go it? in advance.

provided have set correctly, should see on scope while i2cdetect scans i2c bus available devices.

i2c built such nack after writing i2c-address if try talk address doesn't exist on bus. how i2cdetect knows device of specific address doesn't exist on bus. can't see actual data transactions without having device on bus. see i2c user manual.

i suggest attach simple i2c device such rtc (like ds3231m or ds3232m) or temperature sensor on i2c bus , try interfacing them see actual i2c transaction.

another method (which use) have microcontroller known-good i2c-slave implementation act loopback on bus.


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