Syzygy Cape Details

Are there any “blank” Syzygy daughtercard PCB designs available (ideally for KiCad), or maybe a mechanical drawing for the BeagleV-Fire that includes the connector and mounting hole locations? I can probably extract what I need from the gerber files for the Fire, but that’s tedious and somewhat error prone.

maybe? GitHub - SYZYGYfpga/pcb-templates: Template PCB's for SYZYGY board designs

KiCanvas: https://kicanvas.org/?github=https%3A%2F%2Fgithub.com%2FSYZYGYfpga%2Fpcb-templates%2Ftree%2Fmain%2FKiCAD%2FSZG-TEMPLATE-STD

Those would be great resources if the Fire used a standard Syzygy daughtercard form factor, but it doesn’t look like the Syzygy and Fire mounting holes line up. They are a good place to start for the schematic anyway. :slight_smile:

Correct, other then sticking the Syzygy connector, nothing else lines up… i guess we should have had the 2 other mounting holes on the sides…

Regards,

There isn’t room, and I agree with keeping the BBB form factor. The standard TXR4 template from the SYZYGY repo above can be used as-is with the Fire, it will extend past the uSD/CSI end of the board so it’s possible to get to the programming header. I’m debating if I want to make a template to match the BeagleV-Fire PCB or just use the existing template.

Actually, it’s almost trivial to use the gerber viewer in Kicad, although I’m sure any gerber viewer is fine. The footprints for the connectors may be downloaded from Samtec. You will note that both connectors plug and receptacle have two mounting pins, when mated they pins are not coaxial but on opposite sides of the long axis of the connector.

Find the mounting pins on the PCB visible from the opposite side of the connector. Then refer to the mechanical drawing to find the offset. This is the magic number you’ll need for placement of the mating connector.
X=66.3654, Y=15.5238 The 0,0 coordinate is the lower left mounting post and the SYZYGY connector at the lower right.

It would be nice to have these coordinates confirmed, although I should have a PCB soon enough.

Yes, I used KiCad’s gerber viewer to get measurements and pull the board outline into a PCB file but I’ve decided I’m just going to use the standard SYZYGY board layout. That puts the expansion board sticking off the end of the Fire which means I don’t have to put SMT parts on both sides of the board. Since I’ll probably have to use a stencil & oven (the SDI parts I need to use are tiny and very fine pitch) it will be much easier to not have parts/connectors on both sides of the board.

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