About MC33772C using daisy chain wake-up problem

[claire_chen]

The BMS uses ADI's LTC6820 connected to the MC33772C with a daisy-chained wake-up, but no wake-up.
The MC33772C goes to INIT after power on, waits for 60S, and then goes to IDLE state.
 The communication is normal, and the wake-up timing is the CS pull-down, pull-up, pull-down, pull-up operation of the 6820, but no wake-up. Any suggestions on what to look for in a daisy chain wake-up?

[TomasVaverka]

Hi Claire,

After waking up the first node, you have to initialize it (give a CID number =/ 0; please refer to chapter 11.2 Initialization register – INIT in the datasheet), then wait twu_wait (min 0.75ms) and send a second complete wakeup frame to wakeup the second node, etc...

Also note that your uC needs to send two short CSB low pulses with a fixed delay between them (note the timing in particular of the pause t2 must be between 500 and 700 us).

Please check also the SPI timing.

Please check f and g:

Best regards,

Tomas