Most Atmel AVR microcontrollers can be programmed via their in-built serial programming interfaces (SPI). This method is ideal for in-situ programming, such as might be used in manufacturing or for firmware development or field upgrades.

In this scenario, the micro remains in its socket on the application board and a low-cost in-system programmer (ISP) is plugged into a dedicated programming header. In other words, the microcontroller does not have to be removed from its socket and plugged into a parallel programmer each time a firmware update is required.

However, in some cases it is desirable to program a microcontroller stand-alone, such as when the application board is unavailable or doesn’t include an ISP (or JTAG) header. A low-cost method of stand-alone programming might also be useful where a batch of chips is needed for a small prototype run and the cost of a commercial parallel programmer is prohibitive.

This is where the AVR ISP SocketBoard comes in. It provides the minimum of functions necessary to support in-system programming, including a regulated power supply, clock source and microcontroller IC socket. Just connect your in-system programmer to a PC, plug its ISP cable into the SocketBoard’s on-board header and add a DC plugpack. You’re then ready to start programming!