RPI+PhatDac+Hyperpixel


#1

Hello,
Was hoping to get RPI3B+ PhatDac and Hyperpixel 4.0 screen working together but it seems all GPIO get busy with screen. Any way to get around this?

Thank you for your help.

Tom


#2

Not easily.

Assuming you could switch the function of pins like BCM 18 on the fly without the I2C audio breaking it might be possible, but I haven’t seen it accomplished yet.

It would require losing the least-significant bit (well, technically the third least significant because we’ve already dropped two bits of colour information to get to 18bpp so there’s GPIO for touch input) of the red colour channel. This would probably result in fairly obvious colour-banding since you’d be dropping half the available red values.

Then you’d have to drop the backlight control pin, since that’s i2s frame-sync (L/R), and somehow swap BCM 18 between being LCD Chip Select and i2s Clock.

I’m not going to say it’s impossible, but you’d be better off using a USB DAC.


#3

Thanks a lot for your clear answer and help.
( Obviously same question was already asked and similar answer givern. Sorry for that)

Tom