TCA6408A: How to understand INT resetting function ?

zhuangzhuang hu

Part Number: TCA6408A

Hi Experts,

your datasheet page 20 descript "INT resetting occurs in the read mode at the acknowledge (ACK) or not acknowledge (NACK) bit after the rising edge of the SCL signal. "

i really see INT will reset at ACK, but i don't see any response at NACK. Can you explain what scenarios INT will reset at NACK,it should be better if you can provide waveform.

Thanks !

1 day ago

0 Clemens Ladisch 1 day ago

Guru 325130 points

The /INT signal resets at the ACK or NACK after a successful read from the port register. The I²C master issues an ACK if it wants to continue reading; it issues a NACK if the byte that was read is the last one. Any other NACKs belonging to other registers or devices have no effect.

0 Tyler Townsend 1 day ago

TI__Guru 62398 points

Hi Zhuangzhuang,

Please let me know if you have any additional questions.

Regards,

Tyler

0 zhuangzhuang hu 20 hours ago in reply to Clemens Ladisch

Prodigy 10 points

Hi below is a standard waveform, it shows the successful read, after the ack of repeat slave address, the INT reset. could you give me an example, what kind of NACK will reset INT ? please give me a clear wavefrom. i don't want to have unexpected INT reset.

0 Clemens Ladisch 10 hours ago in reply to zhuangzhuang hu

Guru 325130 points

1110100 is not the address of the TCA6408A. I guess that the /INT resets because the port input voltage changed back to the original value.

0 Tyler Townsend 10 hours ago in reply to Clemens Ladisch

TI__Guru 62398 points

Hi Zhuangzhuang,

Please check the addressing:

Are there any changes to the port-side, like Clemens already commented?

Regards,

Tyler

Interface

Interface forum

TCA6408A: How to understand INT resetting function ?