7500 Surf Contest


I’m having some strange anomalies trying to program the 7500 Surf board.

  1. The UART I/O has intermittent connection. printf statements right after the UART config do not show up in the Terminal. Adding a delay and then printf fixes it, but it shows there is a disconnect between I/O and processor function.
  2. Code that worked perfectly on W6100 fails at various points and leaves the W7500 in an unknown state, as if there is a memory leak. My code compiled size is 20k.
  3. Partially through the code, I create a struct with a couple variables, and then assign numbers to those variables after creation. printf on the structure afterwards shows the assign failed and the variables are blank. I don’t know if this is because the printf I/O is using data before the processor has updated the variables, or if it is actually failing the assign.

I am not optimistic I will be able to have a working prototype for the W7500 Surf contest because of this. Unfortunately, it looks as if there is no way to check the memory using VS coding. I downloaded Thonny which allows you to view heap and stack, however, it uses Python and does not seem compatible with Wiznet 7500.

Thanks for any advice.


I have found that snprintf command is not working. Changed the command to sprintf and it partially works.