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Conference bgsdev::open3d

Title:open3d
Notice:Kits on notes 3 and 4; Documents note 223
Moderator:WRKSYS::COULTER
Created:Wed Dec 09 1992
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1306
Total number of notes:5260

1236.0. "" by H2SO4::GERSBACH (Edwin Gersbach MCS Switzerland) Tue Feb 04 1997 11:37

A customer has problems with his DEC3000/300X with a ZLX-E1 graphics board.
After several updates at same time his application fails. The current
configuration is:

VMS V6.2-1h3
Motif V1.2-3 with ECO1
Open3D V3.5
Bravo3 V5.5
No GKS nor PHIGS installed

when he starts the application, he gets twice the same message with just the
serial numbers beeing different:

X Error of failed request:  BadValue (integer parameter out of range for
operation)
  Major opcode of failed request:  139 ()
  Minor opcode of failed request:  28
  Resource id in failed request:  0x1800079
  Serial number of failed request:  15141
  Current serial number in output stream:  15213

At the same time, two entries are written to the DECW$SERVER_0_ERROR.LOG:

 4-FEB-1997 10:14:02.9 PEX -- 1 floating point execptions detected
 4-FEB-1997 10:14:04.0 PEX -- 1 floating point execptions detected

and then the application hangs.

The same configuration works fine on other systems with Powerstorm or ZLXp-L1
cards. On this system, Bravo V4.5 works fine - only V5.5 causes the problem.

A textfile with the whole DECW$SERVER_0_ERROR.LOG is available on
H2SO4::USER$DISK:[GERSBACH.MOTIF.PROBLEMS.SCHINDLER_26590]MAIL.TXT

Any ideas what this could be caused by?

Edwin
T.RTitleUserPersonal
Name
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1236.1try disabling DMAGYPOS3::EIBLReinhard Eibl @FKR, DTN 865-4027Wed Feb 05 1997 07:4120
Edwin,

the 3000/300 model is the only one with half rate turbo channel (50 MHz).
Due to this there are some strange problems with ZLX-E* cards and DMA.
A simple solution in most cases is: switch DMA off. I don't know if this
solves your customers problem, but is is a try worth.

How to switch DMA off for ZLX-E* ?

for UNIX:
    add the Xserver option  -I -ffbDoDMA 0   in /usr/lib/X11/Xserver.conf
for OVMS:
    in decw$private_server_setup.com define decw$ffbdodma to be 0
    (unfortunately i don't know if it needs to be a symbol or a logical,
    try both)

A value of 0 disables both: DMA write and read,
a value of 4 disables only DMA write, what may be sufficient in some cases.

/Reinhard
1236.2WRKSYS::COULTERIf this typewriter can't do it, ...Wed Feb 05 1997 08:1718
      A number of problems like this have been caused by
      DMA activity with the DEC 3000-300 machines.  There
      has been a long-standing problem with that.  The easy
      way to check for a DMA problem is the following:
    
      > We have recently seen an example of a similar problem.
      > In that case, the solution was to turn off the DMA "writes"
      > under VMS.  We are requesting that you have your customer
      > do the same thing and tell us what the results are.
      >
      > The steps to turn off DMA writes are:
      >
      >      (1) define a system-wide logical "DECW$FFBDODMA"
      >
      >              $ DEFINE /SYS DECW$FFBDODMA 4
      >
      >      (2) [re-]start the DECwindows server