Fire-Lite P K-411UD Windows-Based Off-Line Programming Utility - Manual (Page 10)

About Modems
10 Document #50802 Rev.B 1/5/99 P/N 50802:B
2.2 About Modems
A modem (modulator/demodulator) converts the digital data signals of a computer to audio tones in order to transmit
the serial data over standard telephone lines. The modem also converts the incoming audio tones to digital data that
the computer can use.
Two basic types of modem have been designed for IBM PCs and compatibles:
• direct connect internal modems
• direct connect external modems
The internal modem is designed as an IBM PC compatible expansion card which plugs into the computer's expansion
slot. The main advantage of the internal modem is the relatively low cost.
An external modem incorporates its own power supply and RS-232 interface into a single package. It connects to an
IBM compatible computer through an RS-232 serial cable. The main advantages of the external modem are the sim-
plicity of connection to an IBM compatible computer with an RS-232 serial interface and the ease with which it can
be moved from one computer to another.
Using the Configure Modem window, the PK-411UD can be set to operate with either an internal or external modem
with a baud rate of 1200 or higher. The PK-411UD will set it to the proper baud rate. Baud rate refers to the speed of
transmission in bits per second. Most 1200 baud modems conform to Bell 212A North American standard. Baud
rate standards set guidelines for modem manufacturers to ensure compatibility between modems operating at the
same baud rates.
2.2.1 Compatible Modems
The following internal and external modems are supported:
• Cardinal 14400
• Cardinal 28800
• Hayes Accura 14400
• Hayes Accura 28800
• Hayes Optima 9600
• Hayes 2400 Data/9600 FAX
• Hayes 1200 Smart Modem
• Identity ID-2400
• US Robotics Sportster 1200
• US Robotics Sportster 9600
• US Robotics Sportster 14400
• US Robotics Sportster 28800
• Zoom 14400 Data/FAX
• Zoom 9600