Hi Fernando,
I’m exploring some options for Zynthian-Hat and found out that there is ALTERA FPGA on Zynscreen. I as curious person would like to ask, what for? Display itself is using SPI. Or do you translate SPI stream into parallel access into LCD controller via this FPGA?
Thanks
And next question, have you ever considered to use display as complete Zynthian shield for all essentialities, as MCP, MIDI, I2S populating, maybe alternative power delivery option?
@Mark_OzzMaker, please, could you satisfy @sailort’s curiosity? 
No. Current IC distribution seems OK to me because it eases case-mounting, avoiding too much wiring going from case-top to case-bottom. Currently only the 26-pins ribbon segment connects both parts, and it’s very comfortable to manage. Also, it seems elegant to me having all the “UI-circuitry” in the case-top, while having the processing and audio/MIDI circuitry in the case-bottom.
Regards,
This statement is correct ;
The Altera CPLD acts as shift register and converts the single SPI output from the Pi into a 16 pin input needed by the LCD
So it needs some kind of firmware/code? Is this free or some proprietary closed source?
this is my first attempt (but still work in progress) to achieve this kind of thing:
As said, still a work in progress and it will, quiet for sure, never been achieve. It’s the way I use to learn how to use kicad, freecad and understand how these electronic stuff works.
(*) when using standard components, otherwise it’s +3$ per each non standard component (like wm8731, mcp23017 and so on)
That’s a good start. Please consider optional power input and if possible, audio ins/out on some header in case of eurorack mounting. That’s what I like it to have it Maybe I’ll start to design my own to better help, as there is a lot of dimension constraints as I come so far in mind visualization.
