The Memory Plug is a small board with 1 to 4 EEPROM memory chips. With M24M01’s from STMicroelectronics, the board can have up to 512 Kbyte of memory (4x 1 Mbit).
An I2C bus running at 3.3V is used as interconnect, with all the power and signal lines brought out to to both sides of the board to allow daisy-chaining with other I2C-conformant boards.
The pre-assembled versions comes with one, two, or four SMD-sized M24M01 flash memory chips (i.e. 128, 256, or 512 Kbyte) and the decoupling capacitor already soldered onto the board. Note that no 6-pin headers are included.
The PCB only variant contains just the board for the Memory Plug. No parts, no headers.
As connectors you can use a Plug Headers set with 10 male and 10 female 6-pin headers, which makes it easy to connect multiple plugs and JeeNodes in a “standard” way. Or you can solder the board directly in place for more permanent use.
The documentation and full design details are freely available.