Raspberry Pi HAT - 32 I/O Port Expander - MCP23017 - I2C - Black

I was very excited to get my hands on these boards, but I was kind of disappointed with their documentation for Windows 10 IoT or lack thereof..I purchased first IO extender, which came as a kit to be assembled (all components in a box). After assembling it, which took a couple of hours, with having no documentation about the positioning of the components on the board and watching only the provided pictures on NationElectronics web site, I discovered that it works only if I set it on address 0x26 and 0x27. If I was setting it up to anything else, the board will recognize both devices as they were on the same address.I thought I did something wrong while soldering it, so I went and purchased another one, this time an already assembled IO extender board.To my surprise, this one works correctly.I event took the time to test every single combination of addresses. They all work very well.My only issue with Nation Electronics is that they have no support for Windows 10 IoT, no documentation about how to create a .NET app with this device and they provide no .NET libraries for this device. On their site it is saying the C# examples will come soon, but a month later and still nothing.I had to do a lot of internet digging until I found a good library, which I enhanced to allow writing on any Output pin, while preserving the other pins.Anyway, long story short, with the second board working as advertised, I am pleased with their product.I also emailed the customer service and they answered within 24 hours.I recommend the board, but if you are not versatile with soldering, don't buy the one send as a kit.

Nicely made board. The schematic shows that they have taken the time to move out all the goodies from the chips to accessible pins. My only fault would be that if you are using 10 mm standoffs on the Raspberry Pi, the board is just a little higher off the standoff, requiring a washer to have a firm mechanical connection. Also, the output T2 is very close to the second set of USB ports on an RPi3 and the 5 v input T3 requires you to connect prior to screwing the board down on standoffs because it hides behind the first set of UBS ports on an RPi3. I got the assembled model, have not had a chance to check it out completely software wise.

Excellent product. Works as described. I used two of them to add some extra I/O.