dave@arnold.UUCP (Dave Arnold) (11/03/88)
HELP!? Scenario: A NEC 2400 modem (In Hayes emulation mode) connected to a uVax port. Normal terminal characteristics for dialup support: /MODEM/AUTOBAUD/HANGUP... Modem set-up to send responses codes (I need these for outgoing call progress monitoring---The application is a UUCP clone VMS). All modem control signals connected straight through: DCD,DTR,DSR,RING... (I really think the cable is good) 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! NOTE: If I ATQ1 the modem answers correctly, but I need ATQ0 for outgoing call progress monitoring. Questions: Shouldn't the uVax be ignoring these "Result codes" when there is no DCD? What are the VAX and modem saying to each other when the Transmit and Receive lights flash? How can I get a Hayes modem to work bidirectionally? Dave P.S. I have tried TTY_DIALTYPE=1---No go. -- Dave Arnold (dave@arnold.UUCP) Work: Volt Delta Resources Phone: (714) 921-7635 Home: 26561 Fresno street, Mission Viejo, Ca 92691
c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake) (11/07/88)
>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)
Wiley_M_Sanders@cup.portal.com (11/07/88)
We have the same problem with a Smartmodem 2400. I haven't really tried fixing the problem, but I have thought about it a little. It seems to me that, when the modem sends out its RING result code, the autobaud, which expects CRs to establish baud rate, sets the baud to something random. Then all sorts of random stuff happens as VMS sends out the login message, the modem control signals get dropped, etc. I would suggest turning off the Hayes result codes. With autobaud set, VMS is pretty happy dealing with a dumb modem. -w
lewis@pnet02.cts.com (Lewis Dupran) (11/09/88)
I originally had the same trouble with our VAX (using 64 of the Emulex DMF-32
ports). I used a Hayes V.series 9600, Hayes V.series 2400, USR Courrier HST,
and six Mitsuba 2400 baud modems.
Symptoms were the same as you described... If the ports were configured
/modem/hangup (etc) the VAX would answer and dump the line. Special note -
I had the modems in NON verbose mode... the "RING" was NOT being sent by
the modems to fool the VAX, so this was not a factor.
Anyway, to make a long story short, I "bandaged" the problem by setting the
modems to answer on 1 ring, to not give result codes unless they are the
ORIGINATING modems, and on the Hayes 9600, I had the luxury of setting the
port speed to a constant 9600 regardless of the connect speed (the v.9600
has a built-in speed differential buffer).
The only problem after all this was that sometimes the modems would completely
lock-up, and they would be busy tx'ing and rx'ing in a deadlock even though
they were on-hook! This gem was solved by enabling /syspassword so that
nothing (except a ^g) gets from the VAX to the modem until after a syspass
is humanly typed.
The only remaining problem now is that if a user loses carrier and gets
disconnected, the process does not "detach"... it's as if they were hooked
up to a standard serial port. An interesting experiment I did to try and
figure this out was to TURN OFF the modem while a user was in session on
it (nice guy, huh?). The session proved to properly "detach" in that case.
Conclusion: some wiring changes are needed in order to fully support these
beasts, and perhaps even an electrolytic capacitor to hold some pin up longer.
One of these days, I'll get around to taking off the bandage and actually
healing the wound.
UUCP: {ames!elroy, <backbone>}!gryphon!pnet02!lewis
INET: lewis@pnet02.cts.comdave@arnold.UUCP (Dave Arnold) (11/10/88)
In article <2564@tansei.cc.u-tokyo.JUNET>, c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake) writes: > > TTY_DIALTYPE bit 0 only changes the logout sequence. > Check VAX/VMS I/O User's Manual Part 1. No, changing TTY_DIALTYPE to 1 uses CCITT protocol spec. Basically, the RING signal is used. Check VAX/VMS I/O User's Manual Part 1. I still think VMS should be ignoring anything from the modem unless DCD is asserted. -- Dave Arnold (dave@arnold.UUCP) Work: Volt Delta Resources Phone: (714) 921-7635 Home: 26561 Fresno street, Mission Viejo, Ca 92691
c31293@tansei.cc.u-tokyo.JUNET (Kenji Rikitake) (11/14/88)
>From: dave@arnold.UUCP (Dave Arnold) >Message-ID: <232@arnold.UUCP> >References: <227@arnold.UUCP> <2564@tansei.cc.u-tokyo.JUNET> writes: >No, changing TTY_DIALTYPE to 1 uses CCITT protocol spec. Basically, >the RING signal is used. Check VAX/VMS I/O User's Manual Part 1. I think this is not right. TTY_DIALTYPE bit 0 only defines whether the VAX turns off modems immediately after the carrier lost, or waiting for 2 seconds. Setting RING signal available is defined by bit 1, so if you set TTY_DIALTYPE to 2, RING function will be enabled. (Do not use it when you connect PADs; PADs will not send RING signals) Check VAX/VMS I/O User's Manual Part 1. :-) And you can find some new functions in latest (Micro)VMS release notes. -- 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)