Init Strings for Common Applications

Many software applications that use your modem must have an init string. An init string is what tells your modem how to act. Every software application will require certain things of your modem. The init string is what tells your modem to act in a certain manner. For most applications, your software application will have a modem pick list. In those cases, you can select your specific modem from the list. If your modem is not listed, then you can select on that is most compatible to your modem. If you have an internal modem but your software only lists the external version, you can select that as your modem choice. The internal modems and the external modems should use the same init string. If your software does not list any choice that works with your modem, you can also try using Hayes Compatible setting. If your software does not have a modem pick list, in most cases you can use the default init string of AT&F&C1&D2. That resets your modem to factory settings and configures it for optimum usage under most circumstances. If this still does not work, you would want to contact the software manufacturer for the requirements of their application. They would be able to tell you what their software requires from the modem. Knowing these requirements, we can then assist you with tailoring your init string to fit your software's requirements.

The following is a listing of init strings for some of the most commonly used applications.

Smartcom LE, Smartcom Fax, Smartcom Data/Fax Pro

The Hayes Smartcom software that ships with our Hayes modems and the commercial versions of the software, contain a modem pick list. Which includes selections for your Hayes modem. You would select your modem from the list of the closest matching modem. The rest of the software configuration would be left up to your individual tastes.

Native Win95 / WinNT applications that use TAPI

An additional note about the newer OS's Win95/98 and WinNT v4.0 - which use a modem interface called TAPI. This feature enables the OS to store all the relative modem settings in one location, and then allows all your communications software to access these settings. No longer will you need to worry about init strings or settings for your modem for each package - provided that your new communications software is TAPI compliant. With the modem's correct INF/driver installed into the OS - your communications software can access the modem's information through the TAPI interface.

Configuring Hayes Modems for Sync Mode (DTR Dial)

The most common synchronous configuration is called "DTR Dial" mode. This means the modem will automatically dial a number stored in its profile and make a synchronous connection as soon as your software (or terminal or whatever) raises DTR.

To configure the modem for this, send the modem the following strings:

The modem should respond "OK" to each line except the last one. It will appear to have gone dead after the last one, but that's normal, we just turned its echo and result codes off. Also of course, you should replace "nnn-nnnn" with the number you want it to dial. You can include things like "9," as part of that if you're on a PBX and need to dial 9 to get out, etc.

The last thing you should do is "dumb strap" the modem. As procedure for this varies from model to model, consult your manual to find out exactly how to do it for your modem. On an ULTRA or older OPTIMA (metal case), you do this with the dip switches. Underneath the front face plate, just to the left of the lights, you'll find a bank of 4 dip switches. For normal operations (including while you're sending the above strings) all four switches should be up. *AFTER* you've sent the above commands though, you need to set dip switch number 1 in the down position. The modem should now be ready. Also remember that should you ever need to reprogram the modem, you'll need to set that switch back to the UP position before it'll respond to AT commands again.

Hayes Modems and Leased Lines

Only the Hayes OPTIMA Business Modem, Hayes ULTRA Smartmodem and Hayes Smartmodem 9600 V.32 support leased line mode.

To set two of these Hayes modems for leased line, take the following steps:


1. Designate one modem as "answering" and the other as "originating". It doesn't matter which is which, or where each is placed, but one must generate answer tone while the other is in originate mode.
2. Send the answering modem the following string: AT&F&L1S0=1&Y&W
3. Send the originating modem the following string: AT&F&L1&Y&W
4. Disable command recognition on both modems. This procedure varies on different models, so please consult your manual for the exact procedure. On the OPTIMA Business Modem this is done with the AT%DUMB1 command. On an ULTRA Smartmodem, set dip switch number 1 to the down position. This should be done *after* you've sent the above setup strings. The remaining 3 switches stay in the up position. You'll find the dip switches on an ULTRA Smartmodem underneath the front face plate just to the left of the lights.

You can test this configuration by hooking the modems up "back to back". Take the telco cable that came with the modem and run it from the line jack on one modem to the line jack on the other. When you power the modems on, they should sync up and get a carrier with each other.