In order to work reliably with text-to-text 'phonecalls, you need to ensure that the modem is properly configured as well as WintextCom Personal Information Manager(tm), otherwise you will experience a high incidence of calls not getting through, or even be unable to connect altogether.

Configuring the modem is the purpose of the "pm:" setup directive following the closing angle bracket in the default WintextCom configuration string. What follows the colon in this directive is the "modem initialisation string", a series of commands sent to the modem to set it up for whatever purpose, in this case, text-to-text calls. The initialisation string is sent to the modem whenever WTC becomes the active application, when it is first started or subsequently switched to. With this setting, which is recommended for general use, the initialisation string is sent to the modem in the background, WTC does not indicate it, so there is no interruption to your operation. There is also no problem about waiting for the initialisation string to be sent to the modem, since if you try to dial or answer a call before modem setup is complete, WTC automatically waits until the modem is ready before sending the necessary command. This is the reason why, on occasions when dialling or answering immediately after activating the directory, you may notice a slightly prolonged delay in the first part of the progress window confirmation.

There are two special characters used in modem initialisation strings in WTC?

The tilde ('~') character causes a half second pause in transmission of the string. This can be useful to ensure the modem is not overwhelmed. There is quite a proliferation of these pauses in the string suggested by WTC, which may not be necessary. They will not do any harm, you can experiment if you wish.
The exclamation mark ("!") is used to send a carriage return (CR) to terminate a modem command line.

The above special character rules apply in other situations where a string is defined for transmission to the modem, such as the answerphone message. You can send an exclamation mark itself by including two consecutively ("!!"), which causes one exclamation mark to be transmitted rather than translating them into carriage returns. However, consecutive tildes result in consecutive half second pauses, allowing you to build up a longer pause; to transmit the tilde itself you need to use the character embedding feature described in the configuration and customisation section of the user manual.

Almost all modems that you will come across today support the "AT command set". WintextCom Personal Information Manager(tm) can be configured to work with non-standard modems, but the default configuration assumes AT compatibility. The software is also preconfigured for the UK's National Telephone Relay Service for the Deaf (Typetalk), and the modem setup dialogue attempts to determine a modem initialisation string for Typetalk compatibility.

After successfully detecting the presence of a modem when you open the modem setup dialogue, WTC communicates with it and suggests the modem initialisation string displayed after "pm:" in the port number edit box. The chances are that this string is correct for you to make and take calls through Typetalk, with other people using WTC or similar textphone software, and with common textphone devices like the QWERTY phone. In that case, all you need to do is add any configuration preferences for answerphone or Braille or whatever and click OK or press ENTER to save the settings, and you are up and running.

However, it is not always so straightforward. WTC attempts to configure your textphone system on the basis of a very common scenario, but if that scenario does not apply in your circumstances, or for other reasons that may cause the automatic setup to fail, this will become apparent in unreliable or completely unsuccessful 'phone operation. If the modem is found but WTC cannot obtain initialisation information, it will present the basic initialisation string:

"~!~AT&F!~~",

which simply attempts to set the modem's default configuration for WintextCom Personal Information Manager(tm) dialling and answering. If you see this initialisation string in the modem setup dialogue, you should expect to have to investigate further, since modem default settings are generally not suitable for textphone operation. The modem settings section under manual setup gives guidelines on configuring your modem with an appropriate initialisation string if the automatic setup dialogue is unable to identify it.

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The Modem Initialisation String