topic PCA9541 10-bit address problem in Other NXP Products

PCA9541 10-bit address problem

yaotienhuang — Mon, 22 Jul 2019 03:58:54 GMT

From PCA9541 spec, the device address can be 0x78 to 0x7C.

However 0x78 to 0x7C are reserved for 10-bit addressing.

So the device address will expand to 0b11110xx 0b1111xxx .

Am I correct?

Thanks.

guoweisun — Mon, 22 Jul 2019 05:59:11 GMT

From PCA9541 spec, the device address can be 0x70 to 0x7F,but from 0x78 to 0x7F is as Reserved I2C-bus addresses must be used with caution.

yaotienhuang — Mon, 22 Jul 2019 06:22:52 GMT

Hi G.w,

If my device address is 0x78, does the address will expand to two byte address? Or still one byte address?

i2c-tools only support to 0x77.

Thanks.

guoweisun — Mon, 22 Jul 2019 06:58:15 GMT

I don't know why your IIC tool only support 0x77 maximum,but this should be still one byte address.