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View Full Version : which STAMP to decode multiplexed BCD?



ieee488
05-14-2006, 06:00 AM
We have a digital panel voltmeter that has multiplexed BCD outputs.
In other words, 4 output pins, a strobe signal, and 4 digits signals.
I want to use a BASIC Stamp to latch that information into something that can be read by a PC.
I hope I am explaining this well.

Looking for a general direction.

THanks in advance.

PJ Allen
05-14-2006, 06:57 AM
A STAMP could definitely handle that job, but which to choose·could depend on how fast that digits strobe is.

ieee488
05-15-2006, 01:53 AM
www.cd4power.com/data/meters/40pc.pdf (http://www.cd4power.com/data/meters/40pc.pdf)
is the datasheet for the panel meter I want to interface to

the strobe signal is only 5usec wide and digits drive signal is 5msec wide

Do any of the STAMP modules have a serial output?
I don't know if I am asking for too much.

At this moment, I am thinking of using five(5) BCD-to-7 Segment decoder/driver ICs and
then using the STAMP to read and convert to something useable and then somehow
be able to communicate with a PC's USB or serial port.

Jon Williams
05-15-2006, 02:06 AM
All Stamp modules have serial output -- catching that narrow pulse is going to be the trickier bit. What I would do is use PULSIN to do it, as PUSLIN returns 0 if there was no pulse captured. If the returned pulse is about 5 you know it's valid, can immediately capture the inputs and send the data with SEROUT.

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Jon Williams
Applications Engineer, Parallax