Saturday, May 17, 2014

Minima VFO - Troubleshooting

Last week I was on Jury Duty, and therefore there was little or no time for my Hobby Projects.

But now, I need to continue troubleshooting my Minima VFO which is reporting an error on the LCD display. The error at program reset is: "Si570 comm error".

As programmed, the Arduino Sketch seems to ignore the error and continues with normal execution. If I remove (unplug) the VFO Module the program "stops" and does not get past the initial start-up stage, and therefore it appears that there is "some" communication with the Si570 (or at least the Pullups work).

My friend Jeff - KO7M, suggested using my BusPirate to ensure that the Si570 was set on the correct I2C address as published and working as expected. This will be easy because of the modular construction that I am using, tests can be conducted on only the VFO Module. This testing would be much more difficult (but not impossible) if everything was built on a single board.
Minima VFO connected to the BusPirate
I am glad I blogged my previous use of the BusPirate, it helped me to remember the commands. I think I will expand that post to be more complete.

Well, maybe it is NOT so easy, because so far, I have not found the VFO problem. In fact, I do not seem to be able to do a simple "scan" for the I2C address.

More troubleshooting needed !



  1. I'm in the same stage of construction, of my minima VFO ... very crazy problem, and stay not solved ;)