Hi
Okay, I can see better what you are trying to achieve.
A couple of more questions.
I'm guessing that when you switch on and start your engine you just have your PC running Serial Tool connected via the UART and it does not transmit anything.
When the "engine" powers up and transmits the dump, Is it a one shot event or does it repeat? If it doesn't repeat can you instigate by sending a command from your PC?
If you know the command to send that returns specific information then things would be a lot easier. If you need to parse through a data "dump" it is a little more complicated. Depending on when/where you start looking, the incoming value could be data or PID or MID etc as they are all just bytes. However the data is in a defined format which you will already know and also the associated parameters.
For example you might have
MID / PID / data / data / PID / data /checksum
The MID/ PID values will be fixed for the line of interest (I am not using real values here) such as
128 / 001 / x / y / 002 / z / checksum where x/y/z are data values
This line will always contain the above with only x/y/z/checksum changing
You could parse through a dump looking for value 128 (MID) and if found the next value should be 001 (PID), followed by two data bytes, then the value 002 (PID) followed by a data byte and checksum. If you found these fixed values in the correct order and the checksum confirmed then you would know it was the line of interest and could use the data. If the MID/PID values and positions etc don't match then the line would be ignored.
If PID 001 was oil temp and 002 was oil pressure from MID 128 then you may have
128 001 123 456 002 321 checksum included in your dump somewhere. You could perhaps create an array called imaginatively "oil" containing seven values. When parsing the dump if it found the value 128 it would place that value in the first position of the array oil[0]=128 and continue to parse. If the next value was 001 then it would place this in the second position oil[1]=001 and continue, but if not it would clear the array and continue looking for 128. Assuming all good we would end up with an array oil[128,001,123,456,002,321,checksum]. If your calculation of checksum matched that in the array then you know the array is good. Now, for oil temp you know the values are oil[2] and oil[3] and pressure would be oil[6] (123,456 and 321 respectively).
There are many ways to look / parse for your particular information, the above was just a simplistic example.
If the scan tool allows you to poll for a particular value(s) then it would be easier to replicate that. Perhaps you could try and capture by monitoring the Tx to see what is being transmitted to the engine? Alternatively perhaps obtain the command from the spec?
Regards
Edit....
I see Bob beat me to a reply
I'm not a programming professional, but I'm good with electronics.
That's why many people started using Flowcode