Hello everyone.  

Following on from my other thread about Watchdog problems when using the WS Zero module and the PM firmware, I hereby show-off my version of this module.

The footprint is exactly the same, but the I/O numbers are different.
This new design is based on the classic MM2 chip, that being the PIC32MX170F256B, and is programmed and used in exactly the same way.

Certain I/O pins on the 170, needed to be on certain pins on the footprint, which is why the pin numbers are a bit all over the place. This board is 4-layer.  Not possible to do on two layer with the size restriction.

See my other thread for reasons as to why this came about.
I will be getting a few of these made, so if anyone is interested....

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Smoke makes things work. When the smoke gets out, it stops!

That's very, very neat!
I've only tried designing with 4 layers a couple of times. I got a price on one of them and nearly fell over so I didn't bother after that. lol

The price on 4-layer is very cheap now.
Not what it used to be.
I'll look it up tomorrow, but it was so insignificant, I never even questioned it as part of the order.

Just for the thread's information, 10pcs of this 4-layer PCB was US$7.20, so 72c per board - VERY cheap.

Naturally, gets more expensive the bigger the board, but the CMM2G2v2 board is 4-layer, and 10pc of that size in 4-layer is still only US$37.60 last time I ordered some(August 2025), so only US$3.76 per 4-layer PCB.  This is just the PCB, not counting any of the components on the CMM2G2v2, but it just lets you see how cheap 4-layer has become.

I agree - 4-layer DID used to be startlingly expensive, but it isn't now.
Even moderately large sized PCB's are very cheap.

It's the 6-layer and 8-layer PCB's that are now hideously expensive.  

Thanks :)
I might have another look at 4-layer now. A bit late for my current project though.

Programmer/Tester PCB: