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Strange behavior w5500 with xmega on SPI [SOLVED]

I am developing an another magical library for w5500. For the most of time the chip works just fine, the spi signals looks normal, but suddently my chip got bricked?

whan i try to send any command the chip does not respond at all (sends only zeros, when it should write data) even why i tried read VERSIONR.

the other odd thing is that before the MISO sends acorgingly 0x01, 0x02, 0x03 as a response to write request, but now i get only 0x00, 0x00, 0x08 0x00…etc?

what does this 0x08 mean?

here is my oscillogram:

Totally bricked, or it recovers after reset/power cycle?

No idea, but sound wrong for SPI transfer. But not all zeros means there’s something at the other end :slight_smile:

There could be numerous causes for such bad behavior - oscillator stops working, you get issue with SPI protocol, you start multibyte data transfer command and it does not finish properly etc.

You attached it in wrong way, not accessible. Try again.

well, I tried two different modules with w5500, both of them have the same issue after w while. power cycle do not do a thing.
I checked on the scope, what is supply voltage on module and it never drops lower than 3,15V. the SPI signals seems normal.

exacly! if the chip keep sends only 0’s then I dont bother asking, but now i have not a clue whats going on.
i tried few different SCK speeds from 4Mhz to 100kHz, to rule out wire crosstalking, but with no effect.(maybe i should use even lower clock?)

according to datasheet, the multibyte commands is controlled by CS pin, i try to read it again.

fixed, also, it is worth mention that this is the first packet ever transmitted after power cycle.also there is what it looks like on the next packets.

Not sure I understood - sounds like your W5500 is totally dead? There could be cases when chip is locked, and usually this condition is cleared after power off and power on.

the oscillogram in the first post is taken right after the 8h unpowered chip. (the first packet after powering on). so it seems that chip is locked internally. (or maybe i start it up to fast or to slow?
first packet is send just about 1,5s after powering on, maybe there is issue?

ok, in desperation i hookup the module to arduino uno , and upload an serwer example, and after few restarts chip unlocks itself and working again

i think i can close the tread now.

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