User's Manual

Programming For The RS232—JTECH Protocol:

To communicate with the Controller, the computer software must send

RS232 1200 baud message information using the following protocol.

RS232 Baud Rate And Settings

1200,N,8,1 (1200 Baud, No Parity, 8 Data Bits, 1 Stop Bit).

RS232 Handshaking-Request To Send (RTS) - Clear To Send (CTS)

• The Controller uses CTS to allow data out of the Host output buffer.

• The Controller does not monitor RTS.

• The Controller requires the host to stop sending data immediately,

when CTS signal switches from high to low. Incoming data are not

monitored while CTS signal is low.

• High-speed serial port drivers may continue to send data after CTS

signal is switched to low. This condition causes data to be lost.

Serial port drivers having settings for the amount of buffered data ,

should be set to 0.

7 Digit Message Format:

Contains six parts:

1. Preamble (3 bytes) 4. Separator (1 byte)

2. Function Bit (1 byte) 5. Pager Message (120 bytes max.)

3. Cap Code (7 bytes) 6. Terminator (1 byte)

Preamble: Is a 3 character hex string that supplies start up synchronization

“padding” between messages IN, an output buffer, and information to the

Controller, that a message is coming. The Preamble is [Chr$(255)].

Function Bit: The Function Bit is the single hex character following the preamble.

This character tells the Controller which bit to turn ON in the POCSAG

message sent. Characters are:

(Hex 01) Non Priority Alert for Numeric Pagers.

(Hex 02) Priority Alert for Numeric Pagers.

(Hex 03) Non Priority Alert for Alphanumeric Pagers.

(Hex 04) Priority Alert for Alphanumeric Pagers.

Cap Code: Cap Code is a seven digit data string which contains the address

information of the Pager to be used.

Cap Code Prefix: Is the first 3 digits of the Cap Code. ONLY Cap Code

Prefixes of 000 and 008-199 are allowed.

If the first 3 digits of the Pagers

cap code are [000], the Controller will convert the last 4 digits (Pager number)

of Cap Code by multiplying by 8.

Example: Cap code information sent to the Controller = [0000111].

The Controller sends to the Pager address [0000888].

If the first 3 digits of the Pagers cap code are not

[000], the Controller will send the

Cap Code information as received.

Example: Cap code information sent to the Controller = [1230111].

The Controller sends to the Pager address [1230111].