Screw shield prevents Adafruit touch screen working on Uno R3

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I have an Uno R3 which works properly with an Adafruit 2.8” capacitive touch screen. However, I then inserted a Duinotech Screw shield between the Uno and the touchscreen so that I could add a real time clock to the setup. Unfortunately the screen then does not work. I only get the screen backlight working. If I touch the screen, it dims slightly, but it does not work. One point which may be relevant – I have soldered across the jumper pads on the touch screen to shift the SDA and SCL pins to the Arduino A4 and A5 pins. This is because the screw shield does not include SDA and SCL.

Has anyone else come across this, or has a suggestion, please?

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Update - I just saw an earlier post where the screw shield did not work with a Mega. The answer was that the touchscreen needed the SPI pins, which the screw shield does not provide.

So the plug-in touch screen is worthless to me if I can’t access any of the Uno terminals. It was suggested that a home-made SPI socket be built. This may be tricky…

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Does the Adafruit display connect to the SPI bus using pins 11/12/13 on the UNO, or the ICSP header?

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Hi David
It uses the ICSP header.

Your question got me thinking - I looked at the Adafruit documentation and it seems that I can solder jumpers to shift the display off the ICSP header onto the Arduino I/O pins. Now I have to work out out how to program the system to recognise the relocation of the pins.

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Can you put a stacking header on the Duinotech screw shield, to extend the ICSP pins up to the display? That would be the easiest thing to do.

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Unfortunately not. There is an ICSP socket soldered at that point which mates into pins on the Arduino below.

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