Alan King <[EMAIL PROTECTED]> wrote:
> Martin Spott wrote:
>> I'm not shure if the current configurable serial interface is capable
>> to do bit-mangling and I'm quite confident that it lacks support for
>> checksumming. But this may come in the future,
>>
> Thanks actually that looks pretty good, and is really close to the
> register then data format that I normally use on my microcontroller
> comms. Only with a channel number and parity, really could just have a
> block number and send 4 or 8 channels at once then parity.
This is a good idea when you have enough speed and bandwidth in every
situation.
We 'designed' this pattern based on the assumption that you might have
_very_ little bandwidth and the probability that you suddenly need to
dynamically reduce the number of channels you are going to transmit.
Have a 5.000 Euro (or more) model airplane in mind. You might prefer
abandoning some not that significant control channels before loosing
the whole aircraft :-)
You also have to consider the delays on the reciever when using a
low-speed link. When the reciever looses too much time waiting for the
checksum (over multiple channels) then the aircraft controls will
'feel' strange. If you transmit the checksum with every packet then the
reciever can start munging the data while the next channel is being
transmitted. Delay is a very significant influence here. That's why we
chose the one-channel-one-packet route.
Cheers,
Martin.
--
Unix _IS_ user friendly - it's just selective about who its friends are !
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