Omega Engineering CN8240, CN8260 manual Chksum, END Char

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CN8240 & CN8260 Series Communications & Options

Digital

Communications Option

Examples of valid numeric representations for a 6 character data field:

Numeric Value

ASCII Representation

3

3.0000

 

000003

 

003.00

100

100.00

 

0100.0

 

000100

3.2

003.20

 

0003.2

Examples of invalid numeric representations for 6 character data field:

(B represents a blank, or a space, character)

Numeric Value

Bad ASCII Representation

Why?

 

 

 

3

BBBBB3

Leading blanks

 

 

are not allowed.

 

3.0BBBB

Trailing blanks

 

 

are not allowed.

3.2

-3.20000

‘-’ is not allowed.

CHKSUM

This is a two character Message Code Numbering System, representing the sum of all the ASCII values of all the characters (excluding the START, CHAR, the END CHAR, and the CHKSM themselves) in the message. The sum is computed using the following formula:

CHKSM = SUM(All Message Characters)%256 % represents the modulus operator.

END CHAR

This is a single character designating the end of the message. For all messages, the character used is <CR>, the carriage return.

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Contents Series Omega.comTM Table of Contents Load Type Voltage Limit Option -AL1, -AL2 Relay, N.O. Alarm OutputOption -C2 RS-232 one-to-one Communications Option -C4 RS-485 one-to-many Communications Options -XP1, -XP2, -XP3, -XP4 Transducer Power SupplyOptions -RSP4, -RSP5, -RSP6, -RSP7 Options -PVSV1, -PVSV2 Process OutputOptions -DIC, -RSP4, -RSP5, -RSP6, -RSP7 Remote Setpoint Option -DICWith Remote Communications Options Wiring diagram for digital communicationsZone Omega+ ProtocolMessage Formats Start CharType character Message Type ErrorType ParamEND Char ChksumRead Response from Controller Read Command to ControllerWrite Command to Controller Auxiliary Response from Controller Auxiliary Command to ControllerWrite Response from Controller Request Message Description Read RequestField Description Type Write RequestField Description Auxiliary Command RequestResponse Messages Write Response Read ResponseCN8240/CN8260 Parameter Codes Auxiliary Command ResponseRAM, Eeprom Number Name Read Write Data Field ValueDigital Communications Option PID Digital Communications Option Digital Communications Option Digital Communications Option Or RTD w/ Decimal Auxiliary CommandsRequest Data Fields Command Retrieve Display Parameter # DescriptionCommand Clear Latched Alarms Parameter # Description CN8240 & CN8260 Series Communications & Options CN8240 & CN8260 Series Communications & Options CN8240 & CN8260 Series Communications & Options Warranty / Disclaimer Temperature