Faster Telemetry

So the radio of the last launch transmitted beeps; in the form of bytes, in the 7bit ASCII code. But we do not need 2^7=128 different characters. We need the alphabet, and numbers. So for that we could use 5bit code. This is called Baudot. I was working on implementing a code, and had assistance of Daniel Richman, which finished the whole code while having dinner. So, i checked the speed increase just now, using the “millis()” code:
The example telemetry string on 50baud was
“$$TBL,167,12:13:14,52.7933,5.1163,14378#3A\r\n”

  • 5 Baudot     6.8 seconds
  • 7 ASCII      8.1 seconds
  • 8 ASCII      9.0 seconds

So between the baudot system and the one i used on HoHoHo-I is almost 20% speed increase on telemetry. The only disadvantage is that i can’t use the “*” character for the checksum. But i will just request to change this character into “#” on the tracker.

You can get the code with me or Daniel Richman, since it’s undergoing updates/tuning
Advertisements
This entry was posted in HoHoHo 2, R&D. Bookmark the permalink.