Add orange to epd7in3e

[missionfloyd]

I noticed that palette index 4 is skipped for Spectra 6 panels. https://github.com/waveshareteam/e-Paper/blob/ecdd8cf7bab311e6e290c84c68d474deafb7ca8d/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd7in3e.py#L183 So I tried sending 0x04, and it turns out it's actually capable of displaying orange.

(Code that created this image)

buf = []
for i in range(7):
    buf += [(i << 4) + i] * int(width * height / 14)

epd.display(buf)

This fills in the missing slot with orange. I've only done it for python because I'm not as familiar with how the C libraries work.

[psiegl]

That is pretty cool! Thanks for the hint, will try it as well. Which Spectra did you use? EDIT: tried on a 13.3' Spectra 6, seems to not work on this one.

[missionfloyd]

I have the 7.3 inch https://www.waveshare.com/product/raspberry-pi/displays/e-paper/7.3inch-e-paper-hat-e.htm

[psiegl]

So, I tried to use orange on a 4.0', 7.3' and 13.3' Spectra 6 EPD. 7.3' -> looks like a charm 4.0' & 13.3' -> overall picture becomes more grayish not nice.