Lately I’ve been get more questions about this module. The github repro has some basic information but not the whole story. Here is the background on the module, some insights and some help to make you build one yourself.
Some time ago I was on the search for a drum trigger module and something to spend my time on. Mutable Instruments share all there products under a open source license. Grids is one of there discontinued modules based on a ATmega328P. This happen to be the same chip that is used by Arduino on there Nano (old one).
These Nano’s aren’t the most expensive and I also keep a few in my drawers. I like working with Arduino’s. Grids PCB’s are avaible on the internet so there wasn’t any need to build a new version. But all those PCB are surface mount parts and non of those uses the Nano. A that chip is a awful thing to solder.
So I thought of build one with through hole components and a Arduino Nano. A bit easier to solder for most people.
The schematics for Grids are public available. But not the files so I started out but just coping it in Kicad. From there on it was PCB design, placing the components and tracing all lines.
I’m still kinda new to making pcb’s and working with Kicad. I have no education on electronics but that’s not holding me back. But surly it was time to ask some help. I enjoy reading Muffwiggler and know there a lot of knowledge there for the Diy community.
Help was there and before that I didn’t know about decoupling caps and how to read these from a schematic.
Why don’t the draw these where the sit but just below on the schematics ??
My designing of the board may seem a bit weird at first (and second..). I wanted to make two board that will fit on top of each other. Otherwise it would be a realy big module. I designed it as one board where I could delete half of the board to make the Gerber files needed for the PCB manufacturer.
In the end I had to do it three times. First time the potentiometer where wrong way round, made a few footprint mistakes and still on the last board there are a few issues. But I got these from the manufacturer
The known issues
- The boards had a few production runs (3) and the last issues where workable. A wire had to be soldered between the tempo pot and ground. Lucky ground was very nearby.
I think I got this sorted on the github repro upload but didn’t order the board myself. Three times was enough. So I hope some will test this and report back to me. Else I still have so minor work to do and a new Github upload is needed.
- The led lights might be a little to bright with the current BOM, It’s a matter of opinion. But if you want to change them. (R25, R26,R27, R28)
- Power header and diodes are tight fit. Might wanna install the diodes last.
- A fellow “Wiggler” reports: The resistor R31 before the LM4040-5V is a 100k in Quinie’s design but a 10k in Mutable Instruments. (I have to double check but trust Mutable Instruments, I could have made a mistake here )
- panel hole for button might be a bit to big or small (depends if you use buttoncaps)
What should I’ve done differently
Well a lot of things maybe, but the files are out there and I can still update the current version. But one thing I would still like to do is matching it with a normal Grids panel layout.
Building It yourself
If you don’t want to order a multiple board (most go from 5 pcb and above) you can always send me a email. I might have few in stock as people keep asking me about it.
You can check my Github repro and order some boards and start from there (BOM below). If you have any question please drop me a email, wiggler message or github issue.
Some Pictures from builders
Thanks to all wiggler that helped on creating this. a special thanks to migueldetrool for doing a lot of testing a providing me with some issues reports.
Bill of Materials