bfuller
Posts: 5
Joined: Fri Feb 05, 2016 2:29 am

Touchscreen Setup

Fri Feb 05, 2016 2:40 am

I have purchased a 7" HDMI and touchscreen from ebay for my new Pi 2 B.

http://www.ebay.com.au/itm/201426004372 ... EBIDX%3AIT

The HDMI video is working but I think I still need to play with some parameters as the displayed text quality is not real good.

My problem is getting the touch screen working. This unit has an SPI interface and I have wired it up but can't seem to get Pi to recognise the existence of the touch input. This subject may have been covered before but searching last just left me confused.

I have enables the SPI in the config file but there is more it seems. Some sort of driver. The display uses the XPT204 chip for the resistive matrix driver.

bfuller
Posts: 5
Joined: Fri Feb 05, 2016 2:29 am

Re: Touchscreen Setup

Mon Feb 08, 2016 1:07 am

Attached I have the pinout of the touch part of the board.

Should MISO and MOSI be directly connected, or crossed over? (based on a Pi -- Arduino diagram, I think direct)
Do I need the T_BUSY connection?
What do I do with the T_IRQ connection

And what driver do I need to make this whole thing work please?

Regards
Attachments
SPI Touch 64kb.jpg
SPI Touch 64kb.jpg (60.54 KiB) Viewed 591 times
SPI Touch 64kb.jpg
SPI Touch 64kb.jpg (60.54 KiB) Viewed 591 times

bfuller
Posts: 5
Joined: Fri Feb 05, 2016 2:29 am

Re: Touchscreen Setup

Tue Feb 09, 2016 5:56 am

Well, I have discovered that the 2046 controller is ADS7846 compatible.
I have loaded the ads7846 overlay and confirmed it is there with lsmod command.
But, still no go. I'm stuck

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