Re: MSCB

[Steven Clayton <smclayto@npl.uiuc.edu>]

Hi Francoise and Julia,

please see my responses below.

On Fri, Jul 29, 2005 at 11:17:47AM +0200, Francoise Mulhauser wrote:
> Hi Fred and Steven,
> 
> The hardware is fully setup for the mscb test. It is on and
> I believe should be working.
> 
> I have checked the program. There were some problems that we
> solved. The setup_env was not properly define for
> snake. Then the MIDAS_ROOT was not define on snake.  Only
> then could I build and start the mscb_scs900_frontend
> program.  However, it is still complainig about a bad
> channel. I noticed that the usb black box has both red led
> on, but not the green led on.

I think one of the lights indicates activity on the bus,
maybe the green one.  The red ones must indicate power on
the computer side and on the MSCB side.

> 
> Then the mwpc program is failing when trying to start.
> 
> Then the odbedit is starting, but does not find any of the
> mwpc chamber in the Equipment.

Try loading the file recover.odb: in odbedit, do
"load recover.odb".

> 
> Finaly, the root program is not installed on snake.
> 
> We will leave the full system on and connected for the
> week-end. Monday is a holiday here. Julia will be back by
> Tuesday and would be happy to work with the system at that
> time.
> We have sofar connected only ADC and DAC #1 (0 in c-code) at
> the moment. She will just change to each channel later on.
> 
> 
> Steven, I need to know where you wrote the DAC and ADC
> conversion number. I have found some numbers in the odb and
> some in the two header file (mscb.h and scs900.h). This will
> be the work that Julia will do for each channel.

The calibration of the channels is set at the top of scs900.c
in the global variables channel_offsets[] and channel_slopes[].
I found these numbers by putting DACn into ADCn and also into
the Fluke or Keithley bench DMM.  Then I had a little program
I wrote, called calib.c or something like that, to sweep the DAC
programming values and record the ADC and DMM readings.  From
this data you can fit a line.

> 
> I will check my mail by monday and hope that things will be
> setup for Julia.
> 
> 
> Thanks and best regards
> 
> Francoise

Best regards,
Steven