While I was researching ESC flashing I ran across a YouTube video of someone using the Arduino 4-way interface and a custom built cable to flash multiple ESCs all at once. The idea is once an aftermarket firmware is flashed to an ESC it needs to be upgraded when new releases come out. There are also other settings that can be changed to help performance in some cases. His setup worked (I can’t find the video to link it…) but I thought it could be improved on by using an Arduino ProtoShield. The cable just seemed a bit flimsy and did not look like it would hold up over time so I ordered the Bare PCB ProtoShield from SparkFun for $4.95.
The software includes this diagram which shows you how to connect the ESCs. All my connectors share a common ground then the opposite pin is connected to the matching Arduino pin with a small piece of black wire.
First four ESC connectors made:
Last four ESC connectors attached on the bottom. I made sure to test continuity with a multi-meter because the connections were pretty close to each other.
After switching the software to SILABS BLHeli Bootloader 4way-if the Read Setup button on the bottom left was able to pull in the three connected ESCs. As you can see they are Turnigy 6A running Revision 14.3.