T.R | Title | User | Personal Name | Date | Lines |
---|
1042.1 | | QUIVER::STEFANI | Elvis is my psychic advisor | Fri Jul 30 1993 01:30 | 8 |
| I don't know about the DEMFA, but all of the PDQ-based adapters (DEFTA,
DEFEA, DEFQA, and DEFAA) all share basically the same firmware image
and they all should support Full-Duplex mode. The DEFEA comes with
management software that allows you to enable FDX mode (it's off by
default). I can't say for the other adapters on how (if) FDX is
enabled.
- Larry
|
1042.2 | | KONING::KONING | Paul Koning, A-13683 | Mon Aug 02 1993 14:43 | 14 |
| Full duplex doesn't have any connection with DMA.
The MAC chip is the same on all the adapters, and that supports full duplex.
For many adapters, you won't get the maximum benefit from using it due to
throughput limitations elsewhere. On some you may not get any benefit; DEFZA
is likely to be one of those, as is DEFQA, simply because the FDDI even in
half duplex can swamp the system for those adapters. However, that doesn't
mean you couldn't turn on the feature if you want it for other reasons.
In fact, there are two benefits from full duplex: increased throughput as well
as reduced latency. Increased throughput depends on adapters and software
that can take advantage of it; reduced latency is available to everyone.
paul
|
1042.3 | How about DEMFA? | TKTVFS::IDO | Naoki Ido, CSC/TOKYO, EWB, DTN 680-2456 | Tue Aug 03 1993 00:36 | 5 |
| Can anyone tell us about DEMFA? I believe DEMFA has already had enough
hradware for supporting FDX. May be it needs some help from the device
driver.
Naoki
|
1042.4 | DEMFA requires new firmware for FDX mode | CVG::TOMASWICK | Joe - VAXcluster Validation/aka CVG | Tue Aug 03 1993 09:07 | 6 |
|
FDX for DEMFA requires updated firmware. This is currently in test
and will likely be released sometime in the fall. The firmware will be
revision 2.0.
Joe
|
1042.5 | | TKTVFS::IDO | Naoki Ido, CSC/TOKYO, EWB, DTN 680-2456 | Wed Aug 04 1993 02:46 | 5 |
| re.4
Great news! Thanks for your info, Joe.
naoki
|
1042.6 | | QUIVER::STEFANI | Elvis is my psychic advisor | Sat Aug 07 1993 22:20 | 7 |
| >>Full duplex doesn't have any connection with DMA.
I realize that Paul. :-) :-) I just used the "PDQ-based" reference
because I knew those cards share much of the same firmware code and
have the firmware support for FDX.
- Larry
|
1042.7 | | STAR::STOCKDALE | | Fri Aug 13 1993 08:26 | 6 |
| On OpenVMS AXP, DEMFA V2.0 will be supported in the next release after V1.5.
Just don't expect 200 mbits since the hardware is limited to considerably
less (I've seen 113 mbits).
- Dick
|