The part of the sentence between the two commas contains supplemental information and can be removed e.g. ;
"But it works very well because I can print both the transmitted and received data without any need to 'interpret' anything".
I am sure there is some grammatical term for this. I wish I had a more formal understanding of grammer.
A 'supplemental information' has been defined as a piece of 'additional clarifying information' which when removed from the sentence, the intended meaning of the sentence does not change. The following rules are there in the English Language Grammar to include 'supplemental information' in a sentence; however, it is the author and context that dictate which one to use.
1. Use a pair of parentheses -- () across the supplemental information :
(and understand both of them)
2. Use opening comma (,) and closing comma (,) across the supplemental information :
,and understand both of them,
3. Use opening en-dash (-) and closing en-dash (-) across the supplemental information :
- and understand both of them -
I personally use the Option-1 as too many commas in a sentence get me lost to align the pronouns with their respective antecedents.
If the poster/author really wants that the 'supplemental information' may stay in his sentence for good reason, the sentence could be presented as:
"But it works very well because I can print both the transmitted and received data (and understand both of them) without any need to 'interpret' anything". This is an elegant form up to now owing to @ardly (K+) .