Half a bit
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Banging on the bits My spi reads getting no hits my timing's not tight something ain't right this driver is giving me fits seriously though, my clock signal is *half a bit* behind my MOSI signal using the ESP-IDF, but bang on using the Arduino framework, I think. At least that's what digging around the internet has strongly implied. I'll know by the 15th when my logic analyzer gets here. I figured out it was a timing issue because I was getting 0xFFFF back for my pixel reads, but sometimes 0x0000, and when I plotted them in a square I got a zebra pattern. Unfortunately I may have to rewrite the entire SPI subsystem under the ESP-IDF if I want this stuff to work. What I don't get is how more people haven't had these problems. I think part of it is nearly everyone uses the Arduino framework except for the hackers, which is unfortunate because the ESP-IDF has a number of advantages. They just need to work the kinks out of it apparently. I've got a lot of code invested in the ESP-IDF but if I can't get this to work I will have no e-paper/e-ink support in my graphics stuff for it because none of the controllers seem to be able to handle the timing being off by half a bit.
Real programmers use butterflies
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Banging on the bits My spi reads getting no hits my timing's not tight something ain't right this driver is giving me fits seriously though, my clock signal is *half a bit* behind my MOSI signal using the ESP-IDF, but bang on using the Arduino framework, I think. At least that's what digging around the internet has strongly implied. I'll know by the 15th when my logic analyzer gets here. I figured out it was a timing issue because I was getting 0xFFFF back for my pixel reads, but sometimes 0x0000, and when I plotted them in a square I got a zebra pattern. Unfortunately I may have to rewrite the entire SPI subsystem under the ESP-IDF if I want this stuff to work. What I don't get is how more people haven't had these problems. I think part of it is nearly everyone uses the Arduino framework except for the hackers, which is unfortunate because the ESP-IDF has a number of advantages. They just need to work the kinks out of it apparently. I've got a lot of code invested in the ESP-IDF but if I can't get this to work I will have no e-paper/e-ink support in my graphics stuff for it because none of the controllers seem to be able to handle the timing being off by half a bit.
Real programmers use butterflies
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honey the codewitch wrote:
my clock signal is *half a bit* behind my MOSI signal
Doesn't that mean you are using wrong SPI Transfer Mode[^]? Configuring a different mode doesn't need any rewrite of ESP-IDF code.
Nope, it's the right transfer mode (Mode 0 in this case) Here's part of the relevant information I've been able to find on this issue ESP32-WROVER-KIT use of SPI master - ESP32 Forum[^]
Real programmers use butterflies
