|
sample rate for optical encoders
We are intending to use one of these, or something equivalent to measure steering angle. I've read through the posts above and I don't think the analysis above is correct.
The device generates 256 pulses per revolution. At 60 rpm, 1 rps, this is 4 milliseconds per pulse. Especially with last year's stamp, there's no chance of sampling fast enough to use this device.
With this year's processor, maybe it will work. Has anyone tried? Or measured how often an interrupt can be serviced under "normal" cpu loads? 4 ms is probably only a few hundred instructions, perhaps close to 1000. I'm a bit doubtful that you can do it without totally consuming the cpu.
If you can tolerate less angular resolution and use the 128 or 64 pulse per rev device, seems like you have a lot better chance of making this work.
Or am I missing something here?
Bill
|