Enter a value on the TDE

Yes, that is possible.
For example, you can use the "Mathematic Instruction" block.

You must make a message text. In the message text you call the parameter V1 of the Mathematic Instruction. Then can change the value of V1 with the keys of the the TDE.

You need to integrate the parameters to be changed in a message text.
If you now want to change a parameter, you need to select the appropriate message text.
When the message text is selected, press the ESC key for longer than 2s. Then, a black bar appears in an input / output field.
With cursor up / down you can choose between several fields.
If you select the field to change, press the OK button (at TDE > Enter).
The black bar turns now in a blinking box. With cursor up / down, you can now change the value at this position, with cursor left / right to switch the position.
When you are finished with the changes, press again the OK button and you will return to the black bar.
Now you can select with the cursor up / down to another field, or press ESC to quit the operation.

For this you can use the analog amplifier.