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I need to read 16 color sensors(TCS3210) one after another. So I am thinking of connecting all the outputs to a single atmega32 i/o pin and selecting a sensor using a demux showing low on the output enable bar of the sensor to be read. So only one is putting output and rest all have their output disabled.

The output is a square wave whose frequency is to be read (I use the hardware timer/counters of the atmega32 to count number of low to high transitions in 100 milli secs to calculate the frequency). So is this is a good idea? Can I connect all the lines together or should I have something in between?

Also I will be connecting a single I/O pin of microcontroller to input pins of all sensor?Again can I do this?

Datasheet link of TCS3210-https://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CEUQFjAA&url=http%3A%2F%2Fwww.taosinc.com%2Fgetfile.aspx%3Ftype%3Dpress%26file%3DTCS3200-E11.pdf&ei=fMpFUY69NITorQfgoIGYAg&v6u=https%3A%2F%2Fs-v6exp1-ds.metric.gstatic.com%2Fgen_204%3Fip%3D117.195.154.23%26ts%3D1363528317182144%26auth%3Dbuy4ggbxloq4plgn33fqat3v75rhqior%26rndm%3D0.48476632428355515&v6s=2&v6t=5038&usg=AFQjCNEQMV_HabUav8aoZYdwWuB5_q9rbQ&sig2=C6l6s2CHkczkSQOrI1ezOQ&bvm=bv.43828540,d.bmk

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It says in the blurb of the device: Output enable (OE) places the output in the high-impedance state for multiple-unit sharing of a microcontroller input line. I can't say if "reading" a frequency is a good idea because you haven't provided enough info. Watch different logic levels in case the device needs/uses 5V and you are needing a 3V3 input. Also watch the time it takes to enable one device after disabling the previous.

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  • \$\begingroup\$ Thanks @Andy aka. I use the hardware timer/counters of the atmega32 to count number of low to high transitions in 100 milli secs to calculate the frequency. So you think its fine? \$\endgroup\$
    – Samyuktha
    Mar 18 '13 at 2:58
  • \$\begingroup\$ @Samyuktha if you are happy with the frequency resolution 100ms gives you then that's the important thing. I didn't look into the device past the Output enable thing \$\endgroup\$
    – Andy aka
    Mar 18 '13 at 7:47

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