Hi All,

    I've been lurking around on this list for a couple years and am finally
about to embark on my first serious PIC project. It is a university project.
A group of aeronautical engineering students and I want to build a tiny
black box for a model airplane, to aquire 8-12 channels of analog data.
Before I ask my questions, here is what I have planned to use so far:

16F877 for 8 channels, 10 bits
24FC256 serial eeprom - 256k of data storage
PICALL Programmer

    This should provide at least 10 min of storage at 30 samples/sec, using
3 bytes for every 2 samples. My main concern is that we may need more
channels, up to 10 or 12. I see at least one 16 and some 17 and 18 series
PICs that are up for the job. I have two concerns about these alternate
chips though, these parts aren't the flash type - I noticed they use the 'C'
denotation instead of the 'F' in their names - does this mean for every code
revision I will need a new chip?

    Also, for the 17 and 18 series chips it seems I will need a different
programmer. Is there a cheap programmer for the 17 and 18 series chips that
I should go with from the start?

    I was also considering using a pin on the 16F877 to switch between two
sets of 8 analog inputs, using eight 2x1 muliplexers. I would read 8
channels into RAM, switch with the muxes, read the second 8 channels to RAM,
and then output to the eeprom. Would that work? I've never heard of
multiplexers switching analog inputs, so I am a little concerned there.

    I'm hoping you guys will point out anything obviously mistaken and maybe
offer some ideas. Sorry if I sound like a total newbie by asking so many
questions, I am one - most of my experience is in computer science and I've
only been reading the EE related stuff, though I have been doing so for a
while. Thanks in advance.

Lindsay

P.S. For the curious, here is some non-essential information, the data we
hope to acquire:
3 axes - Accelerometer
3 axes - Gyroscope
Rudder Angle
Elevator Angle
Aileron Angles - 2 channels
Flap Angle
Engine Speed

The gyroscope and accelerometer (donated, thank goodness!) data will
definitely be acquired, while it is yet to be decided which of the later 5
will be acquired. We'd like to get everything, 12 channels total.

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