Specifications

Troubleshooting and Repair Procedures
190 025-9035AA
Figure 48: External Modem Cable
(The Shield on pin 1 is optional; if used, it should be connected only on one end of the
cable, to prevent ground loops; however, it usually does not cause problems if both ends
are connected).
If any of these lines are missing, ZlinkW probably will not work.
Zetron supports the Hayes Smartmodem 1200 and compatible modems. Zetron does not
support using modems that conform to the “WinModem” standard. These modems use
internal software to accomplish tasks that used be done by hardware units called UARTs.
This can create memory address problems that ZbaseW cannot deal with. The simplest
solution is to use a modem model that still has UARTs.
Modem Setup - Software
Unlike early modems, currently produced modems (that is, 2400 baud and faster) are
configured by software commands instead of switches or jumpers.
We provide a way to send a list of commands to the modem each time you start up the
ZlinkW software. ZlinkW checks to see if a file named
modem.ini exists, and if it does, it
sends the commands in it to the modem before starting up.
If you know what you are doing, it may be possible reconfigure these types of modems so
they permanently keep the configuration information. Each modem manufacturer does
this differently, so we leave this method up to you. If you have configured the modem so
that its configuration parameters are not volatile, the
modem.ini file is not necessary. In
many cases, it is actually easier to configure the
modem.ini file.
One question in the installation process asks whether you have a 2400 baud modem and
want it initialized each time you call. If you say yes, it makes a
modem.ini file which
contains commands that work for most 2400 baud modems. This command string is
currently:
AT&C1&D3X0/V1Q0/E1
DB-25S DB-9S Signal
1 — Shld
2 3 TXD
3 2 RXD
4 7 RTS
5 8 CTS
6 6 DSR
7 5 GND
8 1 CD
20 4 DTR
DB-25S
1
2
3
4
5
6
7
8
20
PC Female Connector
Modem
Male Connector
N.C.