[comp.os.vms] How to change modem polling timing of VMS

c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake) (10/05/88)

I'm using MicroVMS 4.4 on MicroVAX ][.
VMS polls each modems by setting DTR 30 seconds ON and 5 seconds OFF
periodically. And this causes a trouble. I'm using Hayes-compatible
modems as frontends, and I set them to reset when DTRs drop off.
And I recently found it disconnected incoming calls very often,
since VMS turns off DTR whatever modems are doing. <sigh>

I have a question. Does anyone know how to make the polling cycle
longer? (like hit a patch to SYS$SYSTEM:TTDRIVER.EXE) Or are there
anybody who have same problem? Reply on comp.os.vms, or
sending mail to me is greatly appreciated.

-- Kenji
-- 
Kenji Rikitake / Wada Lab., Information Engineering Course 
Univ. of. Tokyo graduate school / Phone +81 3 812 2111 ext 7411
Also assistant sysop of TWICS Co.: office +81 3 351 5977
(uucp/dasnet : Kenji%DCTWCS.DAS.NET@Sun.COM)

taylort@decus.com.au (Trevor Taylor (Graphics SIG Chairman)) (10/13/88)

In article <2484@tansei.cc.u-tokyo.JUNET>, c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake) writes:

> VMS polls each modems by setting DTR 30 seconds ON and 5 seconds OFF
> periodically. And this causes a trouble. I'm using Hayes-compatible
> modems as frontends, and I set them to reset when DTRs drop off.
> And I recently found it disconnected incoming calls very often,
> since VMS turns off DTR whatever modems are doing. <sigh>

I don't believe this should happen if the modem is set up correctly as
well as the terminal port. We use a setting of TTY_DIALTYPE = 1 in
SYSGEN which is required for Europe, UK, Australia, etc., and I don't
think it drops DTR for as long as 5 seconds, only one second. Still,
any dropping of DTR is probably too much ...


> Does anyone know how to make the polling cycle longer?

The SYSGEN parameter TTY_SCANDELTA determines the polling interval.


	Trevor

c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake) (10/26/88)

>taylort@decus.com.au (Trevor Taylor (Graphics SIG Chairman)) writes:
>I don't believe this should happen if the modem is set up correctly as
>well as the terminal port. We use a setting of TTY_DIALTYPE = 1 in
>SYSGEN which is required for Europe, UK, Australia, etc., and I don't
>think it drops DTR for as long as 5 seconds, only one second. Still,
>any dropping of DTR is probably too much ...

Well, I found the reason why VAX dropped DTR. The modem's DSR was
set to always ON: when I reset our modems to keep DSR off when they
were not connected, 99% of troubles were disappeared.

Another problem arises: the LOGOUT/NOHANGUP command does not work
properly. Does anyone know its general behavior on DIALUP terminals?

>The SYSGEN parameter TTY_SCANDELTA determines the polling interval.

Hmmmm. I think I don't have to change it; rather want to solve the
problems in more straight way.

>	Trevor

Anyway, I greatly appreciated your help, Trevor.

-- Kenji Rikitake
-- 
Kenji Rikitake / Wada Lab., Information Engineering Course 
Univ. of. Tokyo graduate school / Phone +81 3 812 2111 ext 7411
Also assistant sysop of TWICS Co.: office +81 3 351 5977
(uucp/dasnet : Kenji%DCTWCS.DAS.NET@Sun.COM)