4 ms·
100μs of jitter is enough to cause major problems if you're bit-banging or doing high-speed closed-loop control. Something like the Bus Pirate is almost trivial
by jdietrich 11y ago
100μs of jitter is enough to cause major problems if you're bit-banging or doing high-speed closed-loop control. Something like the Bus Pirate is almost trivial to implement on bare metal, but a complete nightmare if there's an OS involved.
RTOSes can be extremely useful, but they're not a perfect substitute for bare metal.
http://dangerousprototypes.com/docs/Bus_Pirate http://dangerousprototypes.com/docs/Bus_Pirate
- khedoros 11y agoWell, right, that needs to be a multi-purpose serial interface device, and who knows what crazy timing requirements some sensor or interface chip will need. An example: There are some cheap little radios around. They literally just output a carrier with a binary value encoded on it in a super-simple modulation. Even with an RT device, you've got to keep transmissions very short and include a clock-synch section at the beginning. You can still transmit and receive if your devices have a lot of jitter, but you'll have to kill your transmission rate to keep things working reliably.