On Wednesday, 8 May 2019 09:10:55 BST PeterMerchant via dorset wrote: > I want to connect a few wires to R-Pi GPIO pins in a manner that I can swap > out the R-Pis if I need to. I have been looking for Molex headers but have > not found one that fits. I have glued two ten-way connectors together via a > backing strip with a gap between them , but I don't have any more to use. > Alternatively I am thinking of getting Cyntech GPIO headers and soldering > to the pins. > https://shop.cyntech.co.uk/collections/fiver/products/26-way-female-pcb-mou > nt-connector > > I don't want to just use individual connections because I made an error last > time and got a nice piece of smoky wire.
We have been round this loop at WMT. For the initial prototypes we used a ribbon connector with the unused wires cut off and the 'far' end soldered to Vero Pins on the Veroboard which carried this interfacing devices. I also tried the Cyntech header connectors. Both these solutions proved to be a real pain because you can still connect to the wrong pins on the Veroboard if you really try hard enough and the ribbon or wires just get in the way. We then started to make use of various modules, eg DC-DC Converter, Motor Drive Board and A/D Converter Board. These all arrive with header pins (similar to the Pis) or places where header or Vero Pins can be soldered. What we now have is header pins soldered to all of the modules and also to a small Veroboard that carries ICs that are needed for buffering or level shifting. We make the wires out of pre-made jumper cables (https://uk.gearbest.com/development-boards/ pp_198971.html[1]), stripped from the ribbon that they arrive in, cut to length and crimped with new DuPont connectors at the other end. You really need the crimping tool as well as the crimps and you have to make sure that you get the right kind (https://www.ebay.co.uk/ itm/Dupont-Crimping-Tool-SN-28B-Crimper-Kit-Set-Connectors-Raspberry-PI-Arduino/ 264241871752?hash=item3d860afb88:m:mN2kfx7v7GKadkX4I3w6Vgg[2]). This does add up cost-wise, so you also need to be doing a fair bit of it (we will eventually have about fifteen Pis ant WMT). It also doesn't completely solve the problem of getting the wires onto the wrong connector. However, if your wires are different lengths to suit their destinations, then that helps. You can also get header connector housings that hold up to 10 pins (see the eBay link above), so that helps you to locate the correct places, especially if you have quite a few adjacent pins. For WMT, we are using Pi Zeros so we only populate those GPIO pins that we are using; that also makes it easier to locate the right pins. -- Terry Coles -------- [1] https://uk.gearbest.com/development-boards/pp_198971.html [2] https://www.ebay.co.uk/itm/Dupont-Crimping-Tool-SN-28B-Crimper-Kit-Set-Connectors-Raspberry-PI-Arduino/264241871752? hash=item3d860afb88:m:mN2kfx7v7GKadkX4I3w6Vgg -- Next meeting: BEC, Bournemouth, Tuesday, 2019-05-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk/ New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
