4 Replies Latest reply on Mar 13, 2017 11:09 AM by Intel Corporation

    2.8" TFT @ Galileo 2 --> Too SLOW !




      I attached the 2.8" Adafruit display to the Galileo 2 (by SPI). The Adafruit library was not compatible to the Galileo, but luckily, KurtE ported it to Intel: Support for the Adafruit 2.8" TFT display for Arduino Edison

      Basically, the display works, but in slow motion. After the 1980s, I didn't see those slow screens any more. I tried to tweak the code, improved slightly, but basically I have to say that it is not usable with the Galileo 2. I just want to display text, but live changing values. It is far too slow. For comparison, I wired it also to my old Uno and to my surprise it operates approx. 55x faster !!


      First, I'd like to understand how a 8bit 16 Mhz CPU can be so much faster than a 400MHz, 32 bit CPU ???

      Secondly, I need a solution. I saw in the hints from KurtE that he used later MRAA, which seems to be the linux side of the Intel board. As my sensors are all connected using Arduino libraries, it would be a big effort to port all this to linux. Is there any way to run the sensors with Arduino IDE and the display on linux? (Please forgive if this sounds stupid for you).

      In that case, do you expect a big speed increase of the display? Or do I also need to change to 8bit mode?


      EDIT: I think I found why it's so bad: The SPI clock operates at 8 MHz for 1-2µs, then it waits for approx. 270µs, which seems to be related to CS. But I used already fastGpioDigitalWrite for CS and DC, doesn't help. But again, the Arduino code uses only digitalWrite....