Hi guys,
I'm new to the arduino business and was wondering if there was a way for the arduino to receive TTL pulses from an external device (in my case a spectrometer)? If so, how? And can the arduino be programmed to only accept certain TTL pulses that it receives e.g. the 200th pulse it receives?
Thanks!
Yes. Any of the digital inputs will read a TTL high (nominally 5V) as high, and a TTL low (nominally 0V) as low. And yes, you can write a sketch to count the pulses (rising or falling edges, etc) an ignore the first 199 pulses.
But, I have a feeling there is more to your data than reading the 200th pulse... Is it formatted as RS-232, or something like that?
Sorry, I'm not familiar with the RS232 - basically what it is going to do is ignore the 199 pulses, accept the 200th pulse which will trigger an LED to turn on (since the arduino will be connected to the trigger pin of an LED controller box) and then the data will be seen as absorbance in the spectroscopy software. Does that make sense - and how would you go about writing the sketch - are there examples that can be modified or does it need to be a new one from scratch?
To clarify, the absorbance is measured from the spectrometer, so I think this setup should suffice since I can set the frequency of the pulses coming from the spectrometer to the arduino.
What speed are these pulses comming at?