110711     RQRLDMA: DMA Interlock for RSX  Version: February 1984
 
Submitted by: Herbert J. Bernstein, Brookhaven National Laboratory,
Upton, NY
 
Operating System: RSX-11M V4  Source Language: MACRO-11  Memory
Required: 150 + 15 per driver  Software Required: Digital Equipment
Corporation's RSX-11M Version 4 Release Kit.  Keywords: Tools -
Applications Development
 
Abstract: This is a package for introducing a DMA interlock into
RSX-11M, so that high speed DMA peripherals may be used
under RSX without data lates. Only one device is allowed
to perform a transfer at any given time. In addition to
avoiding data lates, the interlock avoids some of the
more mysterious BRU and DSC failures commonly
encountered when adding third party disks and tapes to
PDP-11's.
 
The release consists of a note, source of RQRLDMA, the
interlock routine, and SLP correction files for versions
of SYSXT, MTDRV and DLDRV from version 4.0 of RSX-11M.
It is highly unlikely that these correction files will
work in later versions of RSX without modification. They
should be taken only as suggestions about how to handle
the problem. No drivers are included with this material.
Even if it did not violate Digital Equipment Corporation's
copyright, it would make it much too easy for someone to
try to mate the wrong level of driver to some later version
of RSX. Inexperienced RSX programmers should not attempt to
use this material.
 
Assoc. Documentation: Complete documentation not included. Contact
your local
Digital Sales Representative for the required RSX-11M
User Manual.
 
Restrictions: Digital Equipment Corporation's RSX driver sources are
required. This program is for expert RSX systems
programmers only.
Modifications required for later versions of RSX-11M.
 
Media (Service Charge Code): Write-Up and Listing (DA), One RX01
Diskette (KA)  Format: FILES-11, 600' Magnetic Tape (MA)  Format:
FILES-11