16 rgb rotary SPI port expander panel - testers?

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hi there, I have had some panels fabricated and am looking for a bit of testing. I have two SPI port expander panels for 16 RGB rotary encoders available if there is someone out there who can use one and is willing to add a bit to the library. offered for free as I need them testing. PM me. Read below first:

RGB populated Encoder board.jpg

these panels are SPI port expander panels, using 8 MCP23s17 chips. The chips are already mounted and addressed, and I have code on GitHub that makes things easy to read and write to the encoders and their push switches. the code uses Sumotoys GPIO Port expander lib.

The panel already has hardware debounce added for the each of the rotary encoders and the push switch.

the panels come with all the SMD parts already mounted on the PCB: MCP chips, resistors and capacitors. only things you need to add are the rotary encoders, bicolour leds (if you want them), and a header pin row.

I will provide pcb as in this image:

these are from the first test batch PCBs and there are two errors:
1. a forgotten short ground trace - which I have rectified with a solder bridge, so not an issue, it works perfectly

2. the resistor for the through hole red led is the wrong value (it is the same as the green led resistor), and if both red and green in the bicolour led are on at the same time, the red is brighter than the green washes out the green. This is not an issue other than the red led is brighter than the green one, and the third colour (mixing red and green) is not really available unless the red chip pin is toggled for a PWM dimming. Not really an option in my book. anyhow, both colours work, just not exactly what i want.

to note.
1. these are polling boards, the interrupts have not been broken out, they work extremely well as polling, and avoids the use of interrupts, which can be tricky to look after
2. there is no logic level shifter on the board. it can work on 3.3v or 5v. if you are feeding the chips, leds and rotaries with 5v, you should use a level shifter on the SPI lines or use a Teensy with 5v tolerant pins. tested on a Teensy 3.5 at 3.3v and 5v, all good.
3. the board is developed for use on euroack projects. As such, the rotary spacing is tight, a good fit for fingers to use, but if the clear knobs that you can buy are added, the spacing is not ergonomic. Used as they are, they are bright coloured rotary shafts, and no need for the knobs.

The rotary shafts are 22mm apart in the x8 direction, and 25mm part in the 2x direction.
The whole panel is 46mm by 183mm.

SUMOTOY library:

My code for the use of board:

video of board here: https://www.youtube.com/watch?v=kYjkCRlhFYI

Oh, thinking of selling a few from the amended / Rev2 batch if there is any interest. Let me know.
All the best
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