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Unread 24-05-2003, 18:54
Lloyd Burns Lloyd Burns is offline
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FRC #1246 (Agincourt Robotics)
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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.