Can you please elaborate a little on your question. Casual googling on "packed data" points me to mainframe/database articles. If you specify your environment i can move this to a more appropriate forum where you can get better answers.
P.S.: Excuse me for my unawareness if packed data is something well known
So if I get you correctly, then you have seven bits which represent more than one value (packed data). Bits 1-3 may be valueA (range 0-7), bits 4-6 valueB (range 0-7), and bit 7 valueC (boolean). Or something like that.
What part are you having trouble with? How are the 7 bits stored? Are you trying to get the stored values out of the packed bit-array or are you trying to turn the packed bit-array into a byte so you can do other things with it?
There's another possibility. US-ASCII only really needs 7 bits per character, since all valid US-ASCII codes are in the range [0,127]. If you store such a number as a byte, the highest-order bit is 0. It's possible to compress your data slightly by omitting that eighth bit and packing the chars in a little more closely. You can fit 8 US-ASCII characters into 7 bytes, with most of the characters stored partly in one byte and partly in another. If we number the bits in each character from 0 to 6, they could be grouped thus:
This is just a guess though. Nikhil, does this sound anything like what you're dealing with?
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