Vermes
Advanced Member level 4
It is a small tool for an electronic-programmer.
Sometimes you need several devices in parallel programming. An example might be two independent systems that communicate with each other. Changes such as in transmitted data frames result in compiling two different sources and programming of two different microcontrollers in order to check the effect of the changes. Manual switching the programmer is annoying. That is why it is good to build a simple switch for AVR programmer. It switches the data lines from the programmer to another device, designated by the microswitches. Switch status is indicated by LEDs. Another configuration is also possible: two devices communicate through the SPI (ISP slot), but for the time of programming, the connection is interrupted and one of the devices is connected to the programmer.
Another idea are simple adapters DIP ↔ ISP for microcontrollers Atmega8, 16 and 32.
Link to original thread (useful attachment) – switch do programatora AVR + adaptery