Emu XL-7 & MP-7 User's Group

Thanks for the clarification; I think I understand what you are saying about the blocks now. I will have to look at it when my head is less fuzzy.
Steve


--- In xl7@yahoogroups.com, Bruno <brunorc@...> wrote:
>
> 2014/1/16 steve_the_composer <smw-mail@...>
> 
> > I don't follow the explanation of blocks. For me, the next data value
> > after the byte pair 00 7F is 01 00.
> 
> 
> Indeed, but here we are talking about sending a stream of bytes (e.g. MIDI
> file) through the File Dump - not pairs! Bytes themselves don't have the 7F
> limitation - in fact, in the MIDI file you can find the bytes with the
> highest bit set (Variable Length Values - check the bottom of this page:
> http://www.ccarh.org/courses/253/handout/smf/). Also, File Dump is not only
> used to send MIDI files, but also samples, which are binary data not
> limited by MIDI standard in any way, thus they can be full of FFs.
> 
> So, to overcome the SysEx limitation, one have to get rid of the highest
> bits - in case they were set. Bytes are grouped by seven, and the highest
> bits of every byte are grouped to form the eight byte. That way we can
> guarantee that no byte will ever be bigger than 7F.
> 
> HTH,
> 
> Bruno
>