Tektronix’s MSO2000 line of oscilloscopes are great tools, and with the addition of a few ‘application modules’, can do some pretty interesting tasks: decoding serial protocols, embedded protocols like I2C and SPI, and automotive protocols like CAN and LIN. While testing out his MSO2012B, [jm] really like the (limited time) demo of the I2C decoder, but figured it wasn’t worth the $500 price the application module sells for. No matter, because it’s just some data on a cheap 24c08 EEPROM, and with a little bit of PCB design it’s possible to build this module for under $5.
The application module Tektronix are selling is simply just a small EEPROM loaded up with an SKU. By writing this value to a $0.25 EEPROM, [jm] can enable two applications. The only problem was getting his scope to read the EEPROM, a problem easily solved with a custom board.
The board [jm] designed is available at OSH Park, with the only additional components needed being an EEPROM, a set of contacts for reading a SIM card, and a little bit of plastic glued onto the back of the board for proper spacing.