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The only major problem we had in the group was getting the
RS232 wireless transmitter and receiver to work. What appeared to
happen in the design of the chip was that the first character sent
was used to wake up the receiver, but this character does not get processed.
Then, any signal that was too long, and therefore appeared to be inactive
by the sender, put the receiver to sleep. We were able to send continous
signals via waveform generator, but actual characters appeared to put
the receiver to sleep. The signals sent and receive would mostly match,
but a small change in pulse width would completely ruin the signal.
We improvised by making a long RS232 cable using 2 DB-9 connectors and
a really long ethernet cable.
The other problem that we had was that we were unable to load our MPC555
software into the flash. This has been a challenge for several groups which
they seemed to have resolved by just loading the software into memory, and then
removing the program cable. However, when we remove this cable, everything for some
reason would fail to function. So, we were forced to keep this cable connected.
Another problem that we had was that the motor was being driven at 7.2 volts
which was too weak to make it go on the ground. None of the 2 groups that
used this motor noticed this problem. The motor required 10 volts which we
were limited by the batteries that were purchased. We did not have a fix for this
and we just demo'ed by propping up the car.
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