W5500 silicon bugs?

Question

Hi, I’m working with a W5500 in MACRAW mode and discovered these strange behaviors: after sending a frame by Sn_CR = 0x20 I read in Sn_IR to ensure the frame was sent. But Sn_IR always reads as 0x20 instead of 0x10. I’m only interested in RECV interrupts and set Sn_IMR to 0x02. But when RSTn goes down then Sn_IR had 0x10 instead of 0x04 when sending an ARP request the Protocol Type field is always corrupted (0x3012 instead of 0x0800)

hjjeon0608 · Answer

Hi, I think you read wrong value. Sn_IR cannot be 0x20. First read version register and check it is right value. Thanks.

Zick · Answer

Error #1: I already checked VERSIONR before. That would be quite weird to have a substantial bug in my spi lib although sending and receiving works flawlessly. Error #2 and #3: what about these?

hjjeon0608 · Answer

All about errors may be occurred by register access, I think. You can access memory correctly, but you cannot access register correctly. So, I recommend to debug SPI lib or check SPI pins by like oscilloscope.

Zick · Answer

Thanks for coming back to me. But before I do access memory I read Sn_RX_RSR to get frame length and read Sn_RX_RD to get start address. How can spi fail on Sn_IR but work for all other registers? I’ve already spent quite a bit of time on debugging and like to get some kind of proof that this behavior can’t be reproduced If you like, do the following test: initialize with MACRAW enable RECV interrupt on socket 0 open socket and send some data loop until Sn_IR == SENDOK That’s where I get an infinite loop.