A ? about the OI compition port

[computhief263]

OK, does anyone know if there is any thing else controled through the compition port besides Auto, Disable, and Channel access

im still learning about the control system and the manuals are very explicet in terms of talking about the the compition port

[rbayer]

As far as I know, those are the only three things it's used for other than supplying power to the OI.

[Josh Hambright]

I am pretty sure it can probably do other things, but as discussed in other threads (search around there have been several long ones recently) IFI has been very protective of it.

Isn't there also some kind of a TIME variable that is passed into the control system through the competition port? I heard that at one time but it may have just been a rumor.

[Lloyd Burns]

I'd doubt there is a time variable going to the OI via the Comp Port - the OI's processor has its own accurate enough crystal or resonator clock, and goes through a loop of 26 ms, sending out a data stream which has a one-byte "serial" number.

This "serial" number is the packet_num, from which delta_t is derived. It is this new-packet-every-26-ms feature which provides all the timing information the naked RC can get.

At most, the arena controller might have provided a synchronization signal, so that all four competitors could send one packet before the next round - this would only be useful if there were only one transmitter, and with the single transmitter sending all four packets, the minimum time-between-packets would be 50 or more ms. Since this is not so, no sync is needed, so we have no need of sync signal, nor even a master clock.

[dez250]

from what i have learned about the competition port is as follows but take it with a grain of salt, for i haven't been able to find any print on this:

The Comp port you can change any of the figures on the other ports from there, so remotely the other ports can be changed along with the other 3 all ready listed. plus if memory serves me right its got one voltage out pin, but I'm not sure. again none of this i am 100% sure on but I'm very sure of it... just if you aren't 100% sure yourself of what your doing don't mess with it, cause IFI wont replace or repair your board for misuse or modification of the ports.

~Mike