Thursday, February 26, 2009

ordered first batch of pcbs

So I ordered my first batch of printed circuitboards today. It's sort of a bummer because SNES pcbs are a little bit thinner than the standard issue pcbs. This means I pretty much couldn't use any of the online specials for cheap pcbs. Also, the FPGA has pretty tiny half mm pitch on the pins, so that is just another extra crazy requirement.

On the upside, since I had to do a special custom order anyway, I made the PCBs have blue soldermask instead of the standard green. That's right, blue PCB, totally awesome.

People are telling me that I won't be able to solder something with such thin pitch. I don't really know if I can either. I guess we'll see when I get the boards in next week.

10 comments:

  1. cool, so the entire unit will be housed on a single pcb?

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  2. That's the plan. I wanted it to fit in an original snes cart too, but... well, maybe for the second revision.

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  3. very cool, so do you plan on selling these things?

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  4. Maybe. Let's see if I can get it to work at all first :)

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  5. I'd be interressed in the schematic if you don't mind. I'm really curious about how you make this work. This is for educational purpose since I'm studing electronic.

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  6. @Mathieu The schematic isn't really notable at all (it's also really messy and i'm not even sure it's correct yet). Basically, all the snes cart pins go to the GPIO pins on the FPGA. All the SRAM addr/data lines go tot he GPIO pins on the FPGA. The SD card slot and the USB port go to the relevant pins on a microcontroller. A couple of microcontroller gpio pins are connected to the FPGA GPIO pins.

    I think the moral of the story is that the interesting stuff is going on in the microcontroller firmware and the FPGA core. I haven't written these yet. I might open source them. Not sure yet.

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  7. But according to the doc I've read about the snes some games use additionnal hardware in the cart to add memory and graphical unit like the super Fx, how do you emulate those?

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  8. Post pics of the PCBs once they arrive, and consider selling prototypes to help fund the project to completion.

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  9. @Mathieu that's what the fpga is for: http://en.wikipedia.org/wiki/Fpga

    @Luke that's not a bad idea. hopefully the first prototype goes well. I'm still waiting for the boards to arrive.

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