ZETRON 748 Technical Manual Download

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Feature Set Reference

160

025-9368H

RS-232 Port Speed

When you want to program the Model 748 using the local serial port, you will need a terminal or a
computer running communication software that supports the ANSI protocol for screen control. Most
commercial communications software will support ANSI terminal emulation. For the Model 748 and
the computer or terminal to communicate you will need to specify how to send and receive
characters. Set the terminal or computer to communicate with 8 data bits, 1 stop bit and no parity
(see your terminal or software manual). Once you have specified these communication parameters in
the terminal or computer you must set the baud rate. The baud rate is the number of bits per second
that the information is sent and received. There are 10 bits per character (a character is any number
or letter that you can type on your keyboard) so 300 baud is about 30 characters per second and 4800
baud is about 480 characters per second. You can easily see the differences on your screen when you
download Call Detail records or system programming. We suggest you set the speed to the
maximum value for your terminal or computer.

Once the baud rate of the terminal or computer is set, the same baud rate must be specified in the
Model 748 using the

RS-232 port speed

command. The Model 748 is capable of communicating at

300, 1200, 2400, 4800, 9600 baud on the local RS-232 port.

Note that the baud rate only affects local programming through the RS232 port (DB-9 on the back),
it DOES NOT change the operating speed of the modem.

How to program it:

Access the Model 748 through your direct connected PC or terminal, or remotely from your PC
connected to a modem via the Model 748's internal modem.

Once connected to the Model 748 and the Main Menu is on the screen, type “3” and press

ENTER

the System Menu will be displayed. Select the item number for

RS-232 port speed

and press

ENTER

The currently selected mode or state will be shown along with a message instructing you to press the
space bar to change the mode or state, and to press

ENTER

to accept the current mode or state. Each

time the space bar is pressed, the mode or state changes. Once the mode or state you desire is
displayed, press

ENTER

to accept it. Note that if you accidentally pass the mode or state you want,

keep pressing the space bar and the Model 748 will wrap around (when the last choice is displayed,
it will return to the first one).

The baud rate is updated each time you exit from the Main Menu (item 7).

The

RS-232 port speed

or baud rate can also be set using from DTMF programming. This is

convenient during installation of the Model 748. It can also be a useful troubleshooting tool if you
are having RS-232 communications problems.

How to program it using DTMF:

Using DTMF either over the air, on the telephone line, or through the local telephone port, enter the
program mode using the program access code (default is 12748).

RS-232 port speed

or baud rate:

Enter:

122# (beep beep)