Corrected Bus Pirate pinout?

We’d like your feedback on a major change to the Bus Pirate firmware. We’d like to restore the pin order to the more logical format found on the va and v1a hardware.

The original pin order for va and v1a hardware was MOSI/CLOCK/MISO/CS on single row of pin headers. Pin 1 (MOSI) is the most often used pin, required for all protocols. Pin 2 adds clock, pin 3 adds dedicated data input, and pin 4 adds chip select. See the protocol pinout table above.

The current pin order on v2go and v3 hardware, as seen on a ribbon cable, is MISO/CS/MOSI/CLOCK. This is a lot less intuitive. When we routed the v2go PCBs with a 2×5 pin header, we didn’t pay attention to the change in signal order until it was too late.

We’ve considered changing it several times, but a few things have stopped us. It will be a fairly involved undertaking to update the firmware and test all the protocols. But the primary reason is that existing Bus Pirate v2go and v3 pinouts won’t match the silk screen on the back.

What do you think? Is it worth the effort and ensuing confusion when the pinout changes?

Join the Conversation


  1. My view is it should match the silkscreen. Regardless if the signals are in a logical order or not.

    What I like about v1a more than the pins order is that it can be plugged directly into a breadboard – it’s a single row connector and right angled (on my one at least), simply ideal. BP v2/v3 seems to be less practical in this regard.

  2. I agree with Michal. It doesn’t matter if the order is logical or not, it’s printed to help you identify the signals and it should stay this way.

  3. i’d agree that the pinout and silkscreen should be accurate. BUT it wouldn’t be too hard to whack a sticker over the top….. no more fault !

    At the end of the day, the few times i’ve used the BP I simply hunt around for the clip that I’ve labelled, so really isn’t a problem I am concerned with – if it makes sense then i wouldn’t be a nay-sayer.

  4. When I hook up the BP I always check the silkscreen while doing it, while it’s true you can simply put a sticker on it I’d prefer not having to, the pinout at the moment doesn’t seem all that illogical to me.

  5. It has to match the silkscreen!
    I’m okay with a sticker as long as no one has to care themselfs to get one…

  6. What they said — match the silk.
    Besides, if you switch the pins then anyone that’s counting on the layout persisting on the other end of the 2×5 cable is screwed. Hard to say if anyone’s actually built something with a 2×5 header on the other end, but…

  7. I concur with above comments – silkscreen should (continue to) match signals!

    Stickers won’t solve the problems at hand. Even if stickers will be easily available (not sure how that can be achieved) there will be confusion for those who have BPs v2go and v3 with older firmware – the documentation will have to reflect both pinouts and becomes a source for even more confusion.

  8. It sound unanimous. It was a lot of work anyways, I’ll just leave it out until a new hardware revision with corrected silk (not that I’m anticipating that).

  9. I don’t know if this is the most appropiate post for commenting this, but I have two suggestions:

    1.- A new hotkey (p for pinout?) that would display the pinout in the console (maybe in some sort of ascii art) would be pretty useful.

    2.- Next revisions could have a polarized connector (those with the notch, I don’t know their name) so it could be impossible to connect the ribbon cable backwards f**ing up the clamp connections (I usually connect the clamps first).


    Metis Adrastea

  10. @Metis, there is actually a patch pending about the pinout. If you can’t wait it is in the forum. However it can’t see how the pcb is routed and depends on the hardware setting in hardware.h. The key would be ‘$’ (need to decide together with ian what it becomes) and should be available when the new bootloader and firmware is out (of beta)

    I stick with most of the people and leave it as is. Correct it in the next revision of the pcb/hardware.

  11. I like the pins the way they are, I don`t want to change the flags I’ve done for the test hooks, nor stick anytihing to the pcb to annotate the change

  12. I’d stick with the silkscreen. Personally I prefer to use BP with the probe kit available at Seeed, but it would confuse people and create all sorts of unanticipated problems.

    If really wanted, you could make an option to switch the headers. That option should be a little hard to get, so that only those knowing what to do would touch it.

Leave a comment

Your email address will not be published. Required fields are marked *

Notify me of followup comments via e-mail. You can also subscribe without commenting.