mark@cbosgd.UUCP (Mark Horton) (06/19/85)
We have gobs and gobs of Penril auto-dial 212 modems. They've worked reasonably well on some old configurations (a Develcon dataswtch and a DZ port) with some funny cabling, but we're just now discovering a pair of misfeatures that are giving us fits. We can't use the Penril as a dialup (e.g. 212 answer-only replacement) because it asserts CD all the time. (This isn't switch selectable.) This causes UNIX to wake up the getty, which prints a banner. The banner contains a CR, which wakes up the penril, which greets the getty. The two then carry on a little conversation, eating up CPU, repeatedly. One trick is to set a switch and have RI wired to CD - it will leave RI high during and after the ring. (This is the funny cabling mentioned above.) This worked on the DZ, but when we moved to a DH, we found out that RI doesn't emulate CD perfectly. RI goes up and down a few times before coming up for good. This drives our DH crazy, waking up the getty and immediately blowing it away with SIGHUP. We are also having this problem on a Bridge CS/1. We can mostly use them as a dial-out, but they have an annoying habit that if I have just connected up (within a few seconds) and type lots of stuff fast, ending in CR, the modem fails to print 10 chars worth of output and instead prints the 3 chars "CR LF >". This drives our UUCP crazy on some hosts, since it types fast and sends CR. Often it will expect login, get it, send uucp, expect ssword, and get neither the echo of uucp nor the ssword, just a >. Does anybody have any advice? Can you confirm that these problems (especially the > one) are really in the Penril? Is there a fix? We have about 24 of these modems in 3 racks, an investment we hate to lose or replace. Mark
taylor@ecsvax.UUCP (Steven Taylor) (06/21/85)
There are at least 3 prom sets for the Penril autodialers in question. The "vanilla" prom set does indeed keep cd high (as best I remember) in order to keep terminals happy. (It was designed to be used with dumb crt's as an outgoing device.) A second version was designed specifically to work with Develcon dataswitches in a bidirectional mode. That is, they could be used on the switch for outgoing calls or incoming calls on the same port. I KNOW that this prom set does not keep cd high, but brings it up in response to DTR coming high. (Remember, the dataswitch does not bring dtr high until it is trying to initiate a call. This difference may be the root of the problem mentioned.) If you need more detailed info on this, I'll be glad to discuss this firmware in detail. Finally, there is also, I understand, a "Hayes compatible" firmware set available now as well. Your Penril rep should be willing to work with you on getting a prom that will work, but you may have to get hin to do some investigation before he will admit that the three version (minimum) really exist. Steven Taylor Distributed Networking Associates Charlottesville, VA 22901 (804) 979-0656