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1MachineElf
I appreciate the depth of this guide.

The display is gorgeous. Why aren't these more common?

mastax
Expensive (this one is $700+), monochrome, fragile, dim, burn-in, high-voltage.
prvc
Why so costly?
flaviut
Pretty much answered by the original question:

> Why aren't these more common?

There's no economies of scale.

Looking at the ad for these in https://www.lumineq.com/technology: "TFEL technology has proven its excellence in applications ranging from monitor and control instruments in deep-sea vessels to operational systems in orbital spacecraft."

prvc
Ok, but's what's the value proposition for a purchaser, compared to cheaper alternatives?
numpad0
Does it look like there are plenty alternatives?
dmitrygr
> ARM SoCs from the early 2000s typically has an LCD controller that is capable of driving STN LCDs. However many of these SoCs are also being deprecated or obsolete.

STM32F4 and STM32F7 series have plenty of cheap chips that support driving STN displays

crest
Good look finding any original STM32 parts at the moment.
dmitrygr
Oh, did I miss RP2040 being ordereable in 100ku quantities?

“Sometimes available” beats “toy” anytime

crest
The code could be improved by using DMA channel chaining instead of an interrupt to reload the two DMA channels.
blacklion
From source:

=== Note that it is actually possible to eliminate this interrupt as well. The PIO and DMA could push pixels out automatically without any CPU intervention. However, I am not doing it here, because precise Vsync interrupts are quite useful. I could switch framebuffers here without any tearing effects. This is also critical to implement FRC for greyscales. ===

ultrarunner
This is really great. I'm struggling to find SAM D5x chips and considering swapping in RP2040s instead. Seeing the flexibility in the PIO here makes that pretty tempting.

What are people using for cheap ($5-$10/ea) displays now?