If you go digging in the Ladt Heather code, you will find references to a 
"luxor" device.  This is a LED / power analyzer device that I built.  It runs 
on a ATMEGA 2561 and uses the TSIP protocol.  I've also implemented the same 
TSIP protocol code on a '328 with 32kB of program memory.  It's not that hard 
to do.  At the lowest level it doesn't take much more code than a NMEA 
processor.  The code sends and receives properly formatted TSIP sentences.  
What gets really fiddly is all the details of trying to faithfully emulate an 
existing GPSDO.

Binary or NMEA you need routines like send_msg_start,  send item (like integer, 
float, double), send_msg_end.  For received messages you need things like 
get_message,  get_item_from_message, etc.  The code to do that is not much more 
complicated for a binary protocol or an ASCII one like NMEA.

Binary messages have the little complication of what byte ordering does the CPU 
and protocol use.  Heather has a find_endian routine that determines the CPU 
ordering for getting values from the received messages and re-ordering the 
bytes to what the CPU expects and the output routines reformat CPU values into 
the byte order that the receiver wants. 

--------------------

>  Writing and *debugging* a binary protocol is a lot more involved than a 
> serial stream. You
can argue that code it code and it’s all trivial. 
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Reply via email to