After configuring Realterm according to the datasheet specifications I was able to read the incoming packets displayed as Hex[space]. I noticed that there was no software control for initializing the sending of the packets from the multimeter; as soon as the send button is pressed data transmits does not stop. This presents possible sync issues but I decided to address them later.
After coding the states, byte-to-number function, and checking functionality I focused on aesthetics. My goal was to make it look as to the original as possible. I found a nice 7-segment display library and overlayed it over a picture of the multimeter's screen.
Picture on the left is what the final (so far) program looks. The text box on the bottom shows the 9 packets coming from the meter in decimal form. These packets are converted based on the data sheet above and display a number on the screen. Syncing is still an issue, connection has to be established first then data has to be sent from the meter, otherwise the program will think the first packet is a different one and count 9 packets from there. I was reading about the RTS and DTR pins and I think something can be done to fix the syncing issue but for now I'll settle with this.
In any case, this program is a good starting point. Custom applications can be made from it to graph data like an oscilloscope, turn on/off things if the values fall within a certain range, etc. Please feel free to contact me with any questions or suggestions. You can find the full code below:
As can be seen on the video, I have to first connect to the correct COM port and then manually activate the meter to start sending data. The readings on the program and the meter's LCD are synchronized as I turn the dial through different modes. The current mode can be seen on the panel above the raw data.
Project files can be downloaded here.