CONTREX CX-1200 - Manual (Page 257)

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Definition of Message Elements
“STX” Signals the start of a transmission. (Host/CX-1200) A single byte ASCII Char (02) “^B”.
“Address” Address of the CX-1200 to recognize and interpret the message. One or two ASCII
characters, followed by a comma, in the range of “0-99”. (“0” indicates a Global Trans-
mission to be received by all controls on the serial link).
“Message Error” (Msg Error) General transmission response from the CX-1200. This is a two character
ASCII HEX number, in the range of “00” - “FF”, which may indicate a serial communi-
cations error has occurred upon receipt of a message transmission.
“Data Field” A field of variable length which contains the data for the function requested. The Data
Field is defined for individual functions through out the following section.
“ ? ” Field terminator requesting response from the CX-1200.
“
,
” Address and Data Field separator.
“ = ” Assignment operator indicating assignment of data to follow, or indicator of a parameter
value to follow.
“
.
” Indicates a Constant Table Read of type to follow.
“!” Indicates a Control Command Send.
“ETX” Signals the end of the message. (Host/CX-1200) A single byte ASCII Char (03) “^C”.
“CRC” (Cyclic Redundancy Check) If CRC Enable is “ON”, a CRC value is calculated and sent
with each transmission. The CRC includes all message data except the STX byte. The
data stream is checked against the CRC at the receiving end. The CRC is a four character
ASCII HEX number in the range of “0000” - “FFFF”.
Note: To conserve space, the CRC field has been omitted on all of the following message definition tables.
If the CRC Enable is “ON”, then a CRC value must be appended to each message transmission
immediately following the ETX character.