ESP8266, a TFT LCD, and a SD Card...Headaches!
Posted: Sat Apr 20, 2019 3:33 pm
This shouldn't be difficult. I've done it using a Arduino Uno, or using my own board designed around an Atmega328p. Having a TFT LCD with a controlled such as the ILI9341, and have it share the SPI with an SD card, has been a no-brainer. But, trying to accomplish the same thing with an ESP8266, such as the 12-E, seems like an impossible mission.
I've read several posts regarding this problem, but nobody has offered a solution -- maybe there is none. Most would just use the internal Flash in the ESP8266. The problem with that is that flash has a limited write cycle lifespan. Thus, using a SD card when writing is frequent, makes a lot more sense -- you can easily replace a SD card.
I've tried some many things to try to make the SD card and the TFT play nice, from using pull-up resistors, to having a separate power source for the ESP and the card and TFT (connected only by Ground), to trying Voodoo. Nothing has worked so far. Some say that it is because the SD card and the TFT have a conflct on how they communicated on SPI. But, if this were the case, the same issue would exist in Arduino UNO. But, it doesn't.
I must mention, as well, that I've tried to solve this problem using Lua in ESPlorer, as well as C in Arduino, and even MircoPython. I have also analyze the signals using a digital analyzer. But, so far, I have come up empty.
I wonder if any one else has run into this and has found a solution for it...Or, is it just impossible?
I've read several posts regarding this problem, but nobody has offered a solution -- maybe there is none. Most would just use the internal Flash in the ESP8266. The problem with that is that flash has a limited write cycle lifespan. Thus, using a SD card when writing is frequent, makes a lot more sense -- you can easily replace a SD card.
I've tried some many things to try to make the SD card and the TFT play nice, from using pull-up resistors, to having a separate power source for the ESP and the card and TFT (connected only by Ground), to trying Voodoo. Nothing has worked so far. Some say that it is because the SD card and the TFT have a conflct on how they communicated on SPI. But, if this were the case, the same issue would exist in Arduino UNO. But, it doesn't.
I must mention, as well, that I've tried to solve this problem using Lua in ESPlorer, as well as C in Arduino, and even MircoPython. I have also analyze the signals using a digital analyzer. But, so far, I have come up empty.
I wonder if any one else has run into this and has found a solution for it...Or, is it just impossible?