klg@njsmu.UUCP (Kenneth Goodwin) (07/30/88)
I recently received specs on the Encore Annex II teminal server and everything looks great except for MODEM Control. And since I plan to buy four of these beasts fully loaded in the near future and one application is modem control, i am a bit concerned about this shortcoming and perhaps might have to reconsider and buy someone's elses...... Annex II supports XON-XOFF, except that you can't use XON-XOFF with UUCP or it messes up the G protocol. So if you need flow controls you need hardware handshaking. And that's the rub, the Annex II's Hardware handshaking "leaves much to be desired". The box by the way has the new 50 pin Telco jack connectors as is the popular fashion these days instead of the annex I's DB-9 (?)'s It supports up to 32 ports using 4 Telco 50 pin connectors. Each port is supported by 6 lines - GND, DTR, TXD, RXD, CTS, and NC (NO care, not used) You wire CD into CTS. For hardware modem control it uses DTR - CD handshaking. UGH!!!!! CD (carrier detect) will never drop from the modem until the phone line drops. and if the Annex II drops DTR to any of the modems that I have, they certainly will hang up the phone line. (And NO I won't use the kludge of fixing DTR high in the modem.) SO, how can Encore claim this box has modem controls? What they really need is two more lines, one for true CD and one for RTS so they can handshake on RTS-CTS and monitor CD for line disconnects. But there is only one free line (the DC line) so how to do it. At this point I am convinced that this Box can't be used to effectively control a modem, Sure you could hack up something that works at the price of true control - but you lose more than you gain. So ENCORE Engineering, How about making the following MOD to the BOX before it gets into wide distribution????? How about setting up another version of the addin card for the additonal ports, so that ports 17-24 AND/OR 25-32 would have at least 8 lines per port instead of 6 so that you would have the 3 extra lines per port to do more realistic modem control. Sure you would have only 6 ports per card instead of 8 (30 ports per ANNEX max instead of 32 with ONE modem control card, 28 per annex with two modem control cards) But at least modems would work right. From: DTR GND NC TxD RxD CTS/CD To: DTR GND Txd RxD CD CTS RTS DSR ^^^^^^^^ Or whatever handshaking lines are most appropriate for true modem controls to function correctly. The ANNEX would then have four possible configurations: 1) 16 Terminal Only Ports 2) 16 Terminal Only Ports plus 8 to 16 ADD IN Terminal Only Ports (1 + 2) are the currently available configurations. (except that it's 16 or 32 ports only currently... 3) 16 terminal only ports plus 6 or 12 ADDIN Terminal/Modem Control Ports 4) 16 Terminal Only Ports PLus 8 Addin Terminal Only Ports Plus 6 Modem Control Ports. I know this would mean some software as well as hardware changes, but how can I (WE "THE NET") convince you that this is really needed? Ken Goodwin Till darkness falls and victory is lost! NJ State Medical Underwriters, Inc.