connect rpi to ospi via cable

[mcconns1]

Hey guys,

I just received my OSPi v1.42+. the Rpi I will be using is a B1+, which was verified using the, cat /proc/cpuinfo command. this command tells me it is rev no. 0x3 which equals model B1+ acording to raspberrypi-spy.co.uk . I was hoping someone could tell me how to connect the Rpi to the ospi via a cable instead of direct connect. Since the Rpi has a 2×13 male connector and the ospi has a 2×20 pin female connector which pins of the Rpi 1-26 connect to pins 1 -40 of the OSPi, I’ll be using male to female jumper wires initially, that I will later convert to a ribbon cable. I will be placing these in separate enclosures, because I will be accessing some of the other Rpi gpio pins for other sensors in the future, which I will gladly share. I also use heat sinks and a cooling fan on my Rpi.

Thank you and Regards
mcconns1

[Ray]

I’ve never heard of the model B1+. I think the only available models are RPi 1 A/B, A+/B+ and RPi 2. From your description it looks like you have the RPi B. Note that OSPi 1.42+ does NOT work with the original A and B models — it only works with A+/B+ or RPi 2. Because the pins are backward compatible, you can still use ribbon cables to connect RPi B with the pin headers on OSPi. However, honestly I think the easiest solution is to just buy a A+, which is the cheapest RPi and it would work nicely with OSPi 1.42+.

[mcconns1]

I hear what you’re saying Ray, but never being the one to take easy, I would like to use what I already have and opt for the cable interconnect method, Is there somewhere I can obtain a pinout of the OSPi 1.42+ 40 pin header and how it interconnects with the RPi A+/B+ or RPi 2. Thank you for a great open source project. heck I would even be willing to swap this OSPi 1.42+ for one of the original OSPi that interconnects with the RPi A/B via cables.

mcconns1

[Ray]

I’ve responded to you on the support ticket. For the record, here is what I said (in case other users need to know):

If you do want to use your current RPi, note that the 2×20 pins are backward compatible with the original 2×13 pins — specifically, the first 2×13 pins on the new RPis exactly match the 2×13 pins on the old RPi.

It’s a bit tricky to explain the wiring without holding one at hand. So I will try my best:
First, open the OSPi user manual:
http://rayshobby.net/docs/ospi14_manual.pdf
On page 3, look at the ‘Plus’ version. That’s how the RPi is plugged into the pin headers. Your model B would be plugged in the same way, except that the yellow RCA connector would block it i the way. Anyways, this gives you an idea of which pin should go to which pin.

In fact, OSPi really only uses the first 2×8 pins (go to page 10, look at the Pin Use graph, that shows which pins OSPi uses). So you just need to get either one 2×8 ribbon cable (male to femal) or two 1×8 ribbon cables to make the connections as described above. That’s all. Hope this makes sense.

[mcconns1]

Thanks Ray,

That is exactly what I was looking for, it makes perfect sense.

Regards,
mcconns1

[Author]

Posts