Xref: utzoo comp.os.vms:9869 comp.dcom.modems:2863
Path: utzoo!utgpu!attcan!uunet!kddlab!ccut!tansei!c31293
From: c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake)
Newsgroups: comp.os.vms,comp.dcom.modems
Subject: Re: VMS modem woes
Message-ID: <2564@tansei.cc.u-tokyo.JUNET>
Date: 7 Nov 88 03:13:54 GMT
References: <227@arnold.UUCP>
Reply-To: c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake)
Organization: TWICS Co., Tokyo, Japan
Lines: 73

>From: dave@arnold.UUCP (Dave Arnold)
>A NEC 2400 modem (In Hayes emulation mode) connected to a uVax port.
>Normal terminal characteristics for dialup support:
	/MODEM/AUTOBAUD/HANGUP...

I guess this setting is OK.

>Modem set-up to send responses codes (I need these for outgoing
>call progress monitoring---The application is a UUCP clone VMS).

If you're using the same modem for remote logon,
setup modems not to send result codes. Since you're using
the autobaud feature, those result codes will clutter up
the LOGINOUT.

Usually, you can enable resut code features by including
ATQ0 within your UUCP clone dialing sequences.

>All modem control signals connected straight through:
>	DCD,DTR,DSR,RING... (I really think the cable is good)

Hmmmm. I think cables are OK, too. :-)

>Problem:
>DTR initially asserted.
>Incoming call comes in and:
>1) DTR high
>2) modem asserts RING
>3) modem sends "RING" text to uVax port (NO DCD)
>4) Transmit and Receive leds flash on my break out box several times
>5) uVax drops DTR
>6) goto 1
>THE MODEM NEVER ANSWERS THE PHONE BECAUSE THE VAX KEEPS DROPING
>DTR!

I think you have set DSR always ON. This will cause the problem.
VMS modem drivers assert that DSR SHOULD BE OFF while modems
wait for incoming calls. If you're using Hayes-compatible modems,
you can change settings by AT&S1.

>NOTE: If I ATQ1 the modem answers correctly, but I need ATQ0 for
>outgoing call progress monitoring.

As I wrote before, you should not set ATQ0 as the default.
You can change it by writing ATQ0 within the UUCP login script.

>Questions:
>Shouldn't the uVax be ignoring these "Result codes" when there is
>no DCD?

I don't think so.

>What are the VAX and modem saying to each other when the Transmit
>and Receive lights flash?

I think VAX treats the RING<CR> message as a logon request. 

>How can I get a Hayes modem to work bidirectionally?

The important thing is to keep modems as transparent as possible.
If you want result codes, turn the feature on when you really want it.

>P.S.  I have tried TTY_DIALTYPE=1---No go.

TTY_DIALTYPE bit 0 only changes the logout sequence.
Check VAX/VMS I/O User's Manual Part 1.

-- 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)