ESP32-S2 Saola: General SPI question
Posted: Wed Aug 04, 2021 8:25 pm
Hello community,
I need your help! I am trying to setup the Saola dev board as little "SPI sniffer", so SPI funktionality is as slave.
I tried solutions in arduino with and without DMA, but it seems my issue has some relation with the "4-bytes bug".
Attached is the complete SPI frame, round about 1550 bytes, but it starts with 1-byte address information, and here is the problem!
The 5 first bytes are:
0x2A, 0x00, 0x00, 0x00, 0x50
Sometimes I got 0x50 directly after 0x2A, sometimes with a random number of "0x00" in between, because the frame is repeated every approx. 40ms
SPI frequency is 8MHz, time between the first 1-byte transmissions, rising and falling edge of #CS, is apprxox 1µs.
Is this issue in general more related to Arduino IDE, maybe due to huge latencys, or also "available" in ESP-IDF environment?
Are the meanwhile workarounds or bugfixes available?
Thank you in advance!
BR
Markus
I need your help! I am trying to setup the Saola dev board as little "SPI sniffer", so SPI funktionality is as slave.
I tried solutions in arduino with and without DMA, but it seems my issue has some relation with the "4-bytes bug".
Attached is the complete SPI frame, round about 1550 bytes, but it starts with 1-byte address information, and here is the problem!
The 5 first bytes are:
0x2A, 0x00, 0x00, 0x00, 0x50
Sometimes I got 0x50 directly after 0x2A, sometimes with a random number of "0x00" in between, because the frame is repeated every approx. 40ms
SPI frequency is 8MHz, time between the first 1-byte transmissions, rising and falling edge of #CS, is apprxox 1µs.
Is this issue in general more related to Arduino IDE, maybe due to huge latencys, or also "available" in ESP-IDF environment?
Are the meanwhile workarounds or bugfixes available?
Thank you in advance!
BR
Markus