Anybody get 2.2" TFT working without Arduino library?

[dwieberd]

I still haven't been able to get the 2.2" display with the ILI9340 controller to comminucate at all. I was wondering if anybody has been able to get it to work, or even communicate, without using the Arduino library. I've done eveything I can think of to get it working and all I ever see back from SPI transactions are zeros. I'm using the same hardware and software routines that work fine with SPI-based flash memory parts. Please help.

[dwieberd]

Ok. I finally did get it to respond with something besides zeros! Turns out I failed to appreciate that the reset line was active low. I'm still getting zeros for various IDs (like manufacturer ID) which is kind of strange, but I can toggle the DISPLAY ON/OFF bit with the DISPLAY ON and DISPLAY OFF commands. Also quite strange that 24 and 32 bit reads require a dummy clock before the MSB, but 8 bit reads don't.

[adafruit_support_mike]

Glad to hear you got it working. Seriously.. debugging TFT hardware/software issues is less fun than it sounds.

Without digging into the datasheet, my best guess WRT the dummy clock is a word-boundary synchronization thing. There are a number of cases where we work with a device and say, "if that's the way you're going to be, that's the way you're going to be."