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PiFACE ***and*** GPIO

Former Member

It would be nice to have access to the GPIO pins with an PiFace in place. One solution would be to desolder the 26 pin female connector on the board and replace it by an "header extender" from Adafruit (i.e. a similar female connector with very long soldering pins that go through the board and allow stacking another board (like the Pi -Cobbler)). My question:

1. is the PiFace board single or multiple layer? (multiple layer would be risky to desolder...)

2. while desoldering the existing connector seems easy, resoldering a new one probably means desoldering (and than resoldering) at least the neighbouring relay, to get access to the solder pads.

Is there an easier solution ?

  • I can't say for sure since information on the Pi-Face seems hard to come by, but from the photos I suspect it's a 4 layer board with internal power and ground.

     

    It'll depend a lot on exactly what you want to connect, and how. The relays look to be relatively higher than a normal pinheader, so stacking another board on top may not work, but connecting a ribbon cable should be ok.

     

    Something I've done before (normally to avoid buying the expensive extended connectors) is to simply solder a two row pinheader on top without even trying to de-solder the existing connector - 26 decent solder joints would be strong enough for most purposes, but you can always fill in with epoxy if you're worried about strength.

     

    Either way, it does look like you might need to remove at least the closest relay to get access.

     

    Desoldering a connector like that from a multi-layer board isn't risky, I've removed the equivalent connector from the Pi itself (just to resolder in onto the bottom) and that's a six layer board. It just takes a little patience, some confidence, a steady hand etc. decent desoldering tools will undoubtably help too.

  • Hi - I mailed the PiFace project and got this response:

    "PCB is two layer -- with the right tools, could probably be desoldered.

    Resoldering is hard with the relay -- it's one of the reasons the

    factory doesn't fit the stacking header.

     

    I think it's very much at the user's risk -- a better option would be to

    use [yet-to-be-released] PiStack"

     

    I'm following up within our organization to see if there is a public timeframe for the availability of the PiStack (e.g. PiRack) which is mentioned in the PiFace Getting Started guide.

     

    Thanks,

    Drew

  • in reply to fustiniadmin

    I'm really quite shocked at a reply like that. Especailly given their 'better option' doesn't exist yet.

     

    Let's face it, the 'right tools' for a two layer board is a soldering iron and a simple hand operated desoldering pump.  If you can cope with desoldering the 26 pin connector, getting the relay out of the way isn't going to cause you any problems.

     

    It's obviously at the users risk, but then so is connecting external stuff to the piface and that's what it's designed for!

     

    Surely "a better option would be to use" the simulator and not have to bother about the nuisance of hardware that might get broken when we try to do something with it.

     

    Have we really become the mindless consumer iphone generation who will never look or think outside their gilded cage ?  And if we ever should do so we'll be politely admonished and told that a better option would be not to do that..

    Or is someone with a PiFace someone who wants to learn something new, possibly right up to finding the limits of what will destroy his device ?  IMHO trying something, and learning from our mistakes when (not if) we make them is hard to beat.