Frustrated by having to poke jumper wires into the socket of my AVR ISP MkII every time I wanted to program a breadboarded AVR, I quickly built an adaptor from strip board. It consists of a 6-pin shrouded header plug and two lines of three header pins.
ICSP Breadboard Adaptor Mounted on Breadboard
Construction is fairly straightforward as you would imagine. First cut a piece of strip board 12 lines by 8 columns, or thereabouts. Make a cut straight down the center.
ICSP Breadboard Adaptor Underside
OK, mine isn’t quite central but you get the idea. Check the cut under a magnifying glass, I have found that this is useful to see any swarf that is creating a short-circuit. You can test the breaks with a multi-meter set to Ohms or Continuity if you like.
Prepare the header pins by pressing down on the plastic to the short end to reveal as much of the pins as possible. I do this with needle nosed pliers. Then feed them through the strip board two holes away from the cut to suit breadboard’s center channel. Solder them in. I tend to solder one pin and then straighten by touching the reverse side and reheating the first connection. Careful not to burn yourself on the heated pin and do this very quickly to avoid the header strip melting.
ICSP Breadboard Adaptor Side View Showing Extended Header Pins
Solder in the shrouded header plug a few holes away from the header pins and straddling the cut. Once it is in place you can solder wires across from the shrouded plug to the header pins. I have developed my own colour code to aid me when connecting up but feel free to use your own. I found a piece of scrap ribbon cable to source my connections from. The colours I use are:
- Red – VCC
- Yellow – MOSI
- Black – GND
- Orange – MISO
- White – SCK
- Brown – RESET
Once you have soldered these connections, double check your soldering with a magnifying glass or multi-meter, just to be sure. Bridging connections is very easy on strip board, something I’ve found out to my cost!
ICSP Breadboard Adaptor In Use
To use the device, find a spare area on your breadboard and place the adaptor so the header pins straddle a channel, just like a DIP Chip would. Press in firmly and then you can connect the programming lines to your project with jumper cables without damaging the programmers connector.
