Experimental Physics and
Industrial Control System

Nick Rees <[email protected]> · Tue, 23 Nov 1999 23:28:44 -1000 (HST)

All,

I am currently about to use a XY566 in a non Epics application. As a
result I was intending to write an Epics independent driver which I was
hoping to make compatible with Epics systems in use, in the hope that it
could also be used as an ANSI replacement of the current driver.

So, I am trying to find out how these cards are used and whether what I
want to do is incompatible with what others are doing.

My intention is that the cards be initialised to sensible defaults, but
that their digitisation sequence and gains be modifiable - either at boot
time or with, in the EPICS world, with a suitable waveform output record.

In addition, I would provide the ability to continuously scan the sequence
specified, or else digitize on a trigger with a programmable delay (either
0 or 10-32 ms with a resolution of 0.5 us). The programmable delay is the
thing I need in our current application.

In trying to understand the current driver I find it is complicated by the
use of three different initialization routines - xy566_init, ai_xy566_init
and ai_xy566l_init, and references to a xy085 board. All these appear to
be fundamentally similar, but subtly different. Can someone (probably Bob)
explain the rationale behind all these to me (probably directly, to avoid
clogging bandwidth).

Another thing is the event counter is initilised in some of these
routines, but I can't find where these events counts are accessed, so I am
wondering whether this is actually used.

Finally, with a real technical point, the sample clock mode register
seems to be set consistently to 0x9525, whereas all the documentation
appears to recommend 0x95a5. To me, this would indeed appear to be a
better choice - otherwise the first number digitised in a sequence would
be a bit ropey. However, I may be missing something.

Anyway, comments and suggestions are welcome.

Cheers,

Nick Rees

Joint Astronomy Centre               Ph:       +1 (808) 961-3756
660 N. Aohoku Place                  Fax:      +1 (808) 961-6516
Hilo, HI.  96720                     Internet: [email protected]

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System