After buying this DMM (VICHY VC99) (32.98 USD) I was curious to see what can be hacked so I open it. After removing all the parts I found below the LCD the IC that control this device: FS9922-DMM4. After searching for cool stuff in the datasheet I realize that it can output the LCD data trough a serial port. The datasheet contains an example of how to make this output serial port using an IR led to insulate the computer from the DMM.

Here is the schematic (Transistor: 2N3906; LED: IR204):


DMM Circuit Scheme

DMM Circuit Scheme




And here is some pictures inside the DMM to see where to attach the cables:

Power Connections

Power Connections
Data Cable

Data Cable
Data Cable in IC

Data Cable in IC
Whole circuit

Whole circuit




In another post I will put the information needed to make the IR receptor. For the moment you can see the final photos and the output data format. To use it in Linux I use the QtDMM.

DMM

DMM

DMM

DMM
Serial Port Data

Serial Port Data
Serial Port Settings

Serial Port Settings