Timing compatability

[zogtrog]

Hi,

     I am working with an existing instrument that collects a lot of analogue signals at slow speeds ( < 2kHz ) using the compact DAQ system. I want to collect digital signals at the same time as part of the same acquisition loop.

Old systems that are still in use, parallel ports on another PC to generate digital control signals. Historically these were read on the acquisition PC through it's parallel ports. I would like to use an NI USB-6501 to read these signals instead, as this way the digital signals can be acquired at the same time  as the analogue signals. Latency of the signals is of critical importance to the scientists making the measurement so all signals both analogue and digital must be in perfect synchrony. Ideally I would to collect 48 digital signals.

Should I use an NI USB-6501 or another module in the cDAQ series and if so which one would be suitable ?

Thanks for any help in advance.

[santo_13]

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@zogtrog wrote:

Latency of the signals is of critical importance to the scientists making the measurement so all signals both analogue and digital must be in perfect synchrony. Ideally I would to collect 48 digital signals.

Thanks for any help in advance.

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To achieve synchrony, you need a sampling clock for Digital signals and 6501 being a low-cost variant, there is no form of synchronization as it supports only software timed tasks.

If you're using cDAQ and have spare slots, you can add DI cards such as https://www.ni.com/en-us/shop/model/ni-9403.html