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There is microcontroller for 2 inputs edge capture ?

There is microcontroller for 2 inputs edge capture ?

There is microcontroller for 2 inputs edge capture ?

(OP)
Hi,
I'm looking for an ATMEL microcontroller which can do edge capture input on 2-inputs. I only found some ones which do edge capture on only one input but I need to do this on 2 inputs (I have two signals).
Thanks to tell me if that I'm looking for exists.

RE: There is microcontroller for 2 inputs edge capture ?

How fast response do you require? Can you explain your requirements ?

<nbucska@pcperipherals.com>

RE: There is microcontroller for 2 inputs edge capture ?

If you can use an additional IC you can clock a Flip Flop with your edge and clear the FF with an output bit.

RE: There is microcontroller for 2 inputs edge capture ?

(OP)
In fact, my 2 signals (from an ADXL202 accelerometer) are PWM signals with a periode of 1ms. Moreover, the 2 signals are 'synchronized' because they use the same triangle wave reference in the duty cycle modulator.
If I am unclear again, here is the link to the application note of Analog Devices I'm speaking about : http://www.analog.com/UploadedFiles/Application_Notes/320058905AN604.pdf

RE: There is microcontroller for 2 inputs edge capture ?

I don't think you will be able to do real measurement:
I suggest calculate the required accuracy and I think
you will find that the ATMEL -- without additional hardware
is too slow.

<nbucska@pcperipherals.com>

RE: There is microcontroller for 2 inputs edge capture ?

(OP)
I calculated, and with an acceptable accuracy I fixed myself, a 1MHz clock for the microcontroller will be right.

RE: There is microcontroller for 2 inputs edge capture ?

1µs in 1ms is 1 part in 1000. That is not very great resolution.

Perhaps you could just use the analogue outputs into a PIC chip with dual 10 bit DACs.

RE: There is microcontroller for 2 inputs edge capture ?

(OP)
I know it's not a very great resolution but I think it will be enough. In fact,I can't do much better because after I will send information by RF (I need wireless application) and I'm limited by its bandwith (only 5kps).

RE: There is microcontroller for 2 inputs edge capture ?

Have a look at the Zilog Z8encore!  I think it has three capture channels.  The development system is almost free.

RE: There is microcontroller for 2 inputs edge capture ?

The Motorola 68HC11, DSP56800, DSP56300 series processors will all do what you need (assuming I understand your requirements correctly).

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