Hello I have a question about CD encoding, on this page the third paragraph under SUBCODES it explains about the PQ subcode data and how there are 8 bits in each frame P & Q being the first two. Now they say P (1bit) gives information on where there is program information, where tracks start, and where the cd ends, fair enough. So at the end of reading 98 frames it has 98 P bits and 98 Q bits of info. My first question is why is this P and Q bit at the end of every frame and not at the end of the sector? wouldn't 98bits or each at the end of the sector accomplish the same thing? why have they set it up like this?
My second question is about EFM ENCODING, how does this encoding work? is there a look up table for all the 8bit-to-14bit equivalents? if so how is it derived? I know in EFM they cannot have less than two bit land or pit and no greater than 10, so is this the deciding factor on the 14-bit codeword?
thanks for any help its much needed and appreciated
My second question is about EFM ENCODING, how does this encoding work? is there a look up table for all the 8bit-to-14bit equivalents? if so how is it derived? I know in EFM they cannot have less than two bit land or pit and no greater than 10, so is this the deciding factor on the 14-bit codeword?
thanks for any help its much needed and appreciated