Experimental Physics and
Industrial Control System

Hi Paul,

 

This is basically a software triggered analogue read. Often ai’s have hardware triggers to tell the ADC to sample – frequently across many channels as you propose. The triggers have to be supported by the driver layer, of course. A software trigger (as you propose) would typically be represented by a binary output record, which would cause the driver to trigger sampling, and the values would be fed back to the Ai records by having them I/O Intr scanned.

 

However, all this needs proper support in the driver. It is best to start off with a board with a driver that supports all this, but otherwise you need to write a suitable driver for your board. In the VME world, we use the Hytec 8401 for this sort of job – the software manual is on the Hytec website: http://www.hytec-electronics.co.uk/PDF/Hytec%20EPICS%20Device%20Driver%20User%20Manual.pdf.

 

There is also some areaDetector work going on to generate a 2-D dataset from multiple triggers across many channels – that may be interesting depending on your use case.

 

Cheers,

 

Nick Rees

Principal Software Engineer           Phone: +44 (0)1235-778430

Diamond Light Source                  Fax:   +44 (0)1235-446713

 

From: [email protected] [mailto:[email protected]] On Behalf Of Stephen Paul
Sent: 23 June 2015 06:37
To: [email protected]
Subject: multi-channel analog i/p