A little while ago, The Pi Hut announced the launch of the ZeroSeg add-on board for the Raspberry Pi. I ordered one but it’s not until now that I managed to actually solder it up and have a play. So, let’s see what you get.
It’s a Zero-sized add-on board which houses two 4-character, 7-segment displays running from a MAX7219CNG integrated chip. It comes in kit form and requires soldering. What? I hear you cry. Soldering? Run for the hills! Now, calm down, it isn’t that bad! 🙂 As a kit, it’s a fair amount of soldering, but it’s what I would call beginners-level soldering. To be frank, the most difficult part is working out which resistor is which! All the components have their correct place and the assembly instructions [PDF] are absolutely first-rate. Richard Saville (Average Man) who designed the board clearly knows the Pi market well – we’re not all experts, and we need clear instructions to put things together. The instructions are heavily illustrated with photographs and the order you need to work in is stated clearly.
It comes with a software library and instructions for installing it.
So what did I think of it?
The hardware is excellent. As previously stated, the instructions for soldering it all together are top-notch with photographs and a clear, sensible order of assembly. Everything fits together well and you’d be hard-pushed to get a piece of tissue paper between the two 7-seg displays: they’re that well-fitting. The most difficult part of assembling any board with a chip on it is getting the legs of the chip to fit in the socket (or directly into the board if there is no socket). It proves to be so with this board, and the trick is to ‘roll’ the chip on a flat surface and push the legs in bit by bit until you get a good match to the socket or holes. I had no problems assembling the ZeroSeg: be careful with the soldering iron and everything will be fine.
Installation of the software is simple, with clear instructions, but a little bit manual for my liking and I would have liked to have seen a simple downloadable script piped through to the shell. It’s just a personal preference, though, and the instructions work just fine.
The software library is good and there are plenty of examples to get you started on displaying text, scrolling text and using the buttons. The buttons are even easier to use if you use GPIO Zero rather than straight RPi.GPIO, but an example isn’t given. Perhaps this could be added for simplicity, but again, I don’t really have any complaints.
Conclusion
If you’re looking for some way of displaying simple text and numbers, this is a good solution, especially at the price of just £10. Be aware that some characters (for instance W and M) are replaced by underscores as it’s just not possible to display them on 7-seg displays. The ZeroSeg, therefore, works best as a strictly numerical display. Richard has done a nice example of using the ZeroSeg to display stats from his WordPress blog which you can see here. I’m really glad I’ve had a chance to look at this add-on board, and I’m looking forward to finding a good use for it attached to a Pi Zero, perhaps mounted on the wall somehow!
The ZeroSeg is available to buy from The Pi Hut for £10.
