3.5" PiTFT touchscreen input device not created

[adafruit_support_carter]

Do you have any other SPI devices we could try testing with? Like a SPI based sensor?

[barclay]

Perfect timing! I just hooked up a BerryIMU+GPS (http://ozzmaker.com/product/berrygps-imu/) which is going to be the primary datasource for the device, and the gyro operates off of i2c and SPI. I've verified that it's returning the correct results, so the SPI pings appears to be functioning.

-B

[adafruit_support_carter]

OK, thanks. So that does seem to indicate it's with the display. See the photo below. I've indicated the chip that we're trying to talk to, but for some reason can't. Can you post another close up in focus photo of just that region?

STMPE.jpg (138.41 KiB) Viewed 273 times

[barclay]

This is about as close as I can get before my camera loses focus:

IMG_4804.jpg (237.93 KiB) Viewed 264 times

[adafruit2]

well its something with wiring for sure....just to check, you're plugging the pitft directly into the pi zero right? and even on another pi zero you never get a TFT display?

[barclay]

I've tested with RPi <-> ribbon cable <-> TFT on 2 different RPis, with identical results. One of the RPis has male headers attached, I can try connecting the screen directly in case the ribbon cable is the issue. I'll see about trying that tonight.

[barclay]

OMG IT'S THE FREAKING CABLE! ALL THIS TIME, WHY DIDN'T I THINK TO CHECK THAT?!

RPi direct to TFT => works.
RPi through cable to TFT => fail.

THIS GUY:

IMG_4807.jpg (10.05 KiB) Viewed 247 times

Now, I'm wondering if it's the cable length, and if the failure will reassert if I get a different cable, or if it's something buggered about that particular cable. Thoughts?

[adafruit2]

could be a bad cable but even if its a good cable, adding that length is not at all recommended!!

[barclay]

What is the maximum recommended length? Ideally I'd like to go short as possible, but I don't have IDC cable crimpers to make my own.

[adafruit2]

3"? we dont know for sure cause we've never tried it :/

[barclay]

Note that the real problem turns out that IDC cables reverse the pins, so it was never connected properly. If I get the chance, I'll try with a thru-cable and see how long it can go.