MSP430 USB Stick Development Tool (EZ430-F2013) – JTag breakout cable

For my next project i decided to try TI low power microcontrollers and for that purpose acquired a $20 development tool: EZ430-F2013 (doc, digikey):

eZ430-F2013 development tool

It consists of a USB dongle and a replaceable breakout board with MSP430F2013 processor on it. The dongle allows programming and debugging (which is super cool coming from arduino world). The are interfacing through the 4 wire JTag/SpyByWire. The purpose of this setup is to familiarize developer with the processor family and development environment and perhaps move them to more expensive programmers and tools. What you can also do is to solder a board header on the processor part of it and connect to other peripherals:

Target board for EZ430-F2013 with header soldered

This all is fine and dandy, however i soon hit it’s physical limitations: my prototype breadboard needed to be very close to dongle and i could not use it to program a stand alone processor. Although the first problem could be solved by USB extension cord, the second one needed a more involved solution:

EZ430-F2013 JTag breakout cable

EZ430-F2013 JTag breakout cable - dongle

This is essentially an extension cable that connects to the dongle on one end and has a breakout pins on the other end. The breakout pins can be connected to the microcontroller on the breadboard which can be some distance away from the dongle. Hopefully with this i can program any 4 wire JTag/SpyByWire based microprocessor and don’t have to shell out $99 for the MSP430 USB Debugging Interface.

Here’s the parts list:

• Development tool: EZ430-F2013
• 0.05″ Female 4 position connection header: LPPB041NFFN-RC
• 3/64″ Heatshrink sleeve: F221B3/64 BK100
• 4 conductor cable
• Ferrite bead (optional for short cable, took mine mini-usb to usb cable)
• Connection pin 22-26AWG: 5-104505-3
• 1/8″ Heatshrink sleeve: Q2-F3X-1/8-01-QB48IN-25

Couple of warnings:
The 4 wire JTag/SpyByWire interface does not have any error correction in it and is not designed for distances of more than 1 foot, so keep your cable as short as possible. There are several tricks to make it work over longer distances, but to be sure just make it long enough to allow for breakout and then use USB extension cord for distance. I have managed to push it to about 3 feet but in retrospect it was probably not worth it. Anyway, to make it longer you can try (courtesy of Ricreations, Inc):

• Use twisted pair cable and twist TCK/Test wire with GND wire
• If you can’t twist the whole cable at least twist them at the end (like i did)
• Use a ferrite bead (like i did)
• Put 220 Ohm resistors in serial with TCK and TDO lines

Enjoy,

Aleksey

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Tags: breakout, diy, electronics, EZ430-F2013, JTag, MSP430, SpyByWire