I have a circuit that works with the ICE200 in place, but when the same code is burned into the 2313 ROM, it is intermittent.
The code takes serial input with a custom baud rate (31250 baud) and outputs the received bytes to a PC using the next higher standard baud rate 38.4Kbaud.
I am testing with an external 2313 that is outputting sequencial numbers at the custom baud rate( 0..1..2- 254..255..0..1) with one tenth of a second between each number sent.
With the ICE200 running, every number gets received correctly and retransmitted to the PC correctly. With the same code burned into the 2313 ROM some sequencial numbers are randomly missing.
Does anyone have any suggestions for what could be causing differences between the ICE200 and embedded code in ROM?