CONTREX CX-1200 - Manual (Page 321)

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SERIAL COMMUNICATIONS TEST P1/2
Use the Serial Communications Test screen to set up the Baud Rate, Frame Format and Record Format that
will be used by the host computer. You can send a byte out and receive a byte on the RS-485 port. These
are decimal numbers. If you want to send ASCII, you must use the decimal equivalent. Likewise, if an
ASCII character is received, it will be displayed as the decimal equivalent (e.g., ‘A’ = 65). Use the SerCom
Errs (MP-91) “help” screen to decipher any errors.
Device Address
Device Address (CP-470) assigns a serial communications address to the CX-1200. This number should be different
from any other units that are on the serial link.
Baud Rate
The Baud Rate (CP-471) determines the serial communications data transfer rate (see list below) in bits/sec. With a 10
bit frame length, the number of frame/sec would be 1/10 the Baud Rate.
1 = 300 bps = 300 Baud 2 = 600 bps = 600 Baud 3 = 1200 bps = 1200 Baud
4 = 2400 bps = 2400 Baud 5 = 4800 bps = 4800 Baud 6 = 9600 bps = 9600 Baud (default)
7 = 19200 bps = 19.2 Kbaud
Frame Format
Frame Format (CP-472) determines the parity, the number of data bits, and the number of stop bits for the serial
communications.
1 = N,8,1 = No Parity, 8 data bits, 1 stop bit (10 bit frame-ASCII or Binary)
2 = E,7,1 = Even Parity, 7 data bits, 1 stop bit (10 bit frame-ASCII only)
Record Format
Record Format (CP-469) determines which type of data format (see list below) will be used for the serial communication.
3 = ASCII2 2 = ASCII 1 = BINARY
CRC Enable
If CRC Enable (CP-468) is set to “ON” (1), you must append a CRC value to all serial communications messages that are
received by the CX-1200 (See Serial Communications: Using Serial Communications). The CX-1200 checks the CRC
value against the the message contents (excluding the “STX”), then calculates a CRC value and appends it to all serial
communications responses. If CRC Enable (CP-468) is set to “OFF” (0), the CX-1200 will ignore any CRC value that
is appended to a message and will not append a CRC value to any serial communications responses.
1 = On (Enabled) 0 = Off (Disabled)
SerCom Char Out
When a new value is entered in SerCom Char Out (CP-473), it is transmitted out the RS-485 serial port at the Baud Rate
(CP-471) and the Frame Format (CP-472). SerCom Char Out (CP-473) is a decimal number.
SerCom Char In
Serial Communications Character In (MP-90) displays the value of the last byte that was received by the Serial
Communications port. SerCom Char In (MP-90) is displayed in a decimal format. SerCom Char In (MP-90) is used
primarily for troubleshooting.
SerCom Errs
Serial Communications Errors (MP-91) displays all serial communications errors that occurred during the most recent
transmission.