One of the drawbacks of most microcontroller programmers is that they need to be tethered to a computer to be useful. With a few exceptions (like the PicKit Programmer-To-Go functionality) almost all programmers are dependent on software to be usable. This Stand-alone AVR Programmer is a handy tool for anyone doing physical installations, mass PCB assembly, or anything else where you need to program a chip without lugging a laptop along. By loading the .hex file created by your development tools onto the SD card, you can then program the targetted AVR microcontroller as many times as you want. This can be very useful if you’re programming more than just a couple chips at a time; a pro tip is to get a pogo-pin adapter so that all you have to do is press the pins against the board and hit the big red button.
When working with subcontractors who are assembling devices you’ve designed, a tool like this can be indispensable in ensuring the correct file gets programmed and there are no programming errors. Even someone with no experience can quickly learn the correct way to orient the connector, and then press the button. If they get the red ERROR light, try again, and/or mark it as needing repair. Otherwise, pack it up and ship it out!
Many subcontractors that do physical assembly may not be familiar with programming microcontrollers, so making the task as easy and error-proof as possible means everyone has a better experience. This board can even provide power to the circuit, so you could have a self-test routine run to verify everything is working correctly and give visual feedback. All it needs is 5V, and you could just attach a USB power bank with a USB-barrel jack cable.
This programmer can also set fuses, and because it uses JTAG it can be used to recover chips that have incorrect fuse settings (unless, of course, the JTAG Disable fuse is set — in that case, you need a separate specialized programmer like the Fuse Doctor). JTAG programming is robust and widely supported on most AVR devices (however, some of the newest lines like the AVRDB series only support UPDI). But if your device supports JTAG, and you need a tool like this, it can be invaluable — and the price is great! Assembly is easy as everything is through-hole. So check it out if you’re interested!