> > hi john, > > regarding the recent NRAO memo on word boundry detection > (in your link below): > > i think the early ATA engineers tested prototype hardware > that didn't use 8/10 encoding in high speed serial links. > (since the data is noise like, one shouldn't need two > extra bits to insure sufficient transitions and detect word > boundries), but they encountered problems, and abandoned them > in favor of 8/10 encoding.
Thanks for the info. I'll pass it along. > > philosophically, i prefer industry standards, > like 8/10 encoding. one can transmit test patterns or any > data one wants; it's more flexible and upgradable, > and doesn't cost much more - it's sometimes cheaper > to stick with industry standards, especially if one > includes NRE costs. and SERDES's have tricky stuff inside - many > of them don't gaurantee specs if you don't 8/10 encode. It's a question of trying to do the job with as little hardware as possible at the digitizer, for reasons of power consumption, cost, and RFI, when it's done on a large scale. For most things, I agree with you that the industry standard encodings are better. > > > best wishes, > > dan > > > > John Ford wrote: >> Thought this might be of interest: >> >> >> New Electronics Division Technical Note >> >> >> EDTN No. 213 >> Title: Word-Boundary Detection in a Serialized, Gaussian-Distributed, >> White-Noise Data Stream >> Authors: Matt Morgan, Rick Fisher >> Date: October 13, 2009 >> >> http://www.gb.nrao.edu/electronics/edtn/index.html >> >> >> >> >> >
