Thanks Vojtech! 73, Skip
Vojtech Bubnik wrote: > > > Hi Skip. > > The DOS executable is here: > http://www.cnunix.com/ftp/hamradio/tapr/software_lib/utils/7plus20.exe > <http://www.cnunix.com/ftp/hamradio/tapr/software_lib/utils/7plus20.exe> > > The source code is here: > ftp://sunsite.unc.edu/pub/Linux/apps/ham/7pl217sr.tgz > <ftp://sunsite.unc.edu/pub/Linux/apps/ham/7pl217sr.tgz> > > 7plus is available as installation package in some Linux > distributions. I was maintaining 7plus installation package and other > HAM applications for SuSE Linux in Prague when I was a student. > > There is one neat thing about 7plus. 7plus files have standard header > and tail. The packet radio modems often snipped out the 7plus sections > from their RX window and stored them into appropriate files. Some > applications even executed the 7plus utility to decompress the data > when all pieces were received. There were even programs, that > extracted 7plus files from monitor. This allowed for multicasting, if > the link quality was good. > > 73, Vojtech > > --- In digitalradio@yahoogroups.com > <mailto:digitalradio%40yahoogroups.com>, kh6ty <kh...@...> wrote: > > > > That's neat, Vojtech. Is there a link to download 7plus? WRAP only > > calculates a checksum for the entire file, and if it will not "unwrap", > > we just resend the whole file. > > > > 73, Skip KH6TY > > > > > > Vojtech Bubnik wrote: > > > > > > > > > > so we developed the Wrap program, which sends a checksum at the end > > > > of the message, and error-free reception can be verified that way. > > > > > > Hi Skip. > > > > > > >From the Packet Radio times, we have a 7plus utility, which splits a > > > longer binary file to multiple parts and adds mild error detection / > > > correction codes. After you receive all parts and run them through > > > 7plus, if there are errors, the application will generate a "request" > > > message, which will identify missing parts to be repeated. > > > > > > 73, Vojtech AB2ZA > > > > > > > > > > -- > > *Skip KH6TY* > > http://KH6TY.home.comcast.net <http://KH6TY.home.comcast.net> > > > > -- *Skip KH6TY* http://KH6TY.home.comcast.net
