tom (11/12/82)
>From microsof!decvax!cca!hplabs!hao!menlo70!sytek!gi!arizona!whm@sri-unix Fri Nov 5 00:14:06 1982 Subject: Trouble with VA3481 Modem Newsgroups: net.unix-wizards,net.dcom We're having some problems with a VA3481 modem. We're using it with a VA821 dialer and VA831 converter. It is being used to dial out and we seem to be unable to connect with modems that do not support the 3400 protocol. A neighboring site has accquired several 3481's and they are having the same problem. Has anyone ever encountered similar problems? I have a creeping suspicion that the software is at fault, does anybody have Unix software that we could use to test our equipment with? Thanks in advance, Bill Mitchell ---------------------------------------------------------------- My problem was the reverse of Bill's article, I couldn't dial Bell 212 sites. Here are the facts: 1. The 3481 is indeed a triple modem, which cycles thru 103, 212 and 3400 style carriers in ANSWER mode ONLY. 2. On output, the type of carrier must be specified. This is accomplished by specifying the modem type as the first character sent to the dialer. In my case I had set up the modem type (in dnd) to be "non-103", so I couldn't dial 212 sites (makes sense?!). 3. The real bite, is that if you want to make a 300 baud call, you must manually throw a switch on the back of the 3481! So, to make the modems work with both 3400, and 212 sites, you need to hack the dialer daemon dnd so that you can specify the "non-default" carrier type. I modified dnd so I could specify the dialer address, modem type and modem address in the phone number requested, by prefacing the number with a "%" character. So when I want 3400 style carrier, the phone number is %003565376 (dialer 0, non-103, modem 0), and when I want 212 style, the number is %403565376. Here's what I changed in dnd.c struct mx_leaves { char *name; char rack,modem; short chan; int file; } pdevs[] = {{"/dev/cua0",'0','0'}, {0}}; /* this is my default -----| dialer address and modem type */ In routine dialit(string) #ifndef FLUKEHACK pc(STX); pc(lp->rack); pc(lp->modem); #else FLUKEHACK if( *string == '%' ){ string++; /*skip percent sign*/ pc(STX); pc( *string++ ); pc( *string++ ); }else{ pc(STX); pc(lp->rack); pc(lp->modem); } #endif FLUKEHACK In routine sanitize(string) #ifdef FLUKEHACK case '%': /* indicates first two digits are rack,modem */ *cp++ = *string; break; #endif FLUKEHACK ------------------------------------------------------------ Now for my observations and opinions: It took me 2 months of on again off again phone calls to RV's technical types, plus sending down "defective" gear to find out, that their manual stinks. And what is really irritating, is that the technical boys didn't know what the problem was. Postscipt: Racal-Vadic wanted more money to fix the "problems"! What a POS. So, "Let the buyer beware." Good luck. Tom Dowling John Fluke Mfg. Co. Inc. decvax!microsof!fluke!tom ucbvax!lbl-unix!fluke!tom