Success!
After a bit of research, I discovered that the Uni-Trend UT61E uses an all-in-one chip that also handles the serial communication. It’s a Cyrustek ES51922 Chip and a bit of googling I found the technical documentation that also describes the serial protocol and data encoding in the serial stream.
Took me a bit of work to get the data to flow from the UT61E and after a fair bit of bit-twidling. I was able to successfully translate the raw data from the multimeter to a useful format.
After I wrote the communication library, I wrote a quick console app to dump the values from the meter.
The meter feeds about 2 samples per second (except in Frequency mode where it seems to slow to 1 sample per second). Not the fastest feed but good enough for most application.
Next step is to write the logic engine to deal with all the features I want to implement.
Hi Tom. I was delighted to see this post using a simple console app to read the DMM data – it’s exactly what I need as a basis for understanding this thing. Would you mind including the source code for this? The code for your more advanced program (now UltraDMM) is way too advanced for my purposes!
Many thanks,
Chris