Hi everyone,

we now have Gabriel's Universe driver working with a "LeCroy ADC1182"
VME board, which is simply an ADC board with 8 channels. We generate
the sample-pulses internally on the board, with the Universe driver.
In short, there is no problem using this board to measure (different)
charges (in parallel). Operation is in A24/D16 mode.

I just thought scientific-minded people might be interested in hearing
real-world applications of the Universe driver (and Linux).

In the meantime, Simone wrote : 

quoted

A second question is about the BLT flag, as I understand is used to
enable block tranfer. Now we don't need it because the board that we use
has only a readout address that take values stored inside internal FIFO;
this lead to about 700ns to read one word, but our hardware people are
thinking about to make a new board, putting everything inside a buffer,
so if I'll had to use this how I have to read? For what I undertand
block tranfer tranfer on read a whole block of data but how can I
specify the size? 

Block transfer is mostly interesting for DMA and burst writes. Actually on
VME block transfers are signaled by a different addres modifier (AM) code
on the bus. You don't tell the length: it is the number of data strobes
cycles while the address strobe is active which determines the length. The
universe will only perform block transfers exceptionally on reads: when
you perform a read which is wider than the programmed VME bus width
(reading 32 bit on VME_A32_BLT(16) for example). It will perform block
transfers on writes, especially if you enable write posting which will use
the internal FIFOs and your processor performs store gathering (PPC750 for
example). 

 We too would like to use block transfers. It does not work however.
 ``Device not configured'' it seems. I just changed (in the VME_window
 struct) VME_AM_A24(16) to VME_AM_A24_BLT(16).
 Unfortunately, I'm no VME expert. So, are BLTs something a VME board
 itself must support ? Or do I need to set another parameter ?

 Any input is highly appreciated,
 
+-----------------------------------------------------------------+
   David 'Septimus' De Ridder     [off-list ref]

"Fortunately, Hill Giants have large blind  spots in
 which a human can easily hide. Unfortunately, these
 blind spots are beneath the bottoms of their feet."
 - 'Hill Giant' (M:TG)
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