TM 5-3895-374-24-2
955-257
5.11 DATA PROTOCOL DEFINITIONS
*
-Standard ASCII character used by the host computer to initiate a command.
:
-Standard ASCII character used as a field separator.
/
-Standard ASCII character used as a separator between the PARAMETER
mnemonic and the data in a WRITE command.
$
-Standard ASCII character used by the controller as the first character
in a response.
UNIT #
-ASCII 0 to 63. The’ unit address Identification is by means of binary
weighted internal switches on the controller communications board. The
unit address can be omitted in transmissions when only one unit is
involved and address switches are set to all zeros. (See Section 5.8.)
R
-READ command
W
-WRITE command
PARAMETER
-Controller variable shown as a three-character ASCII mnemonic. ONLY
UPPER CASE CHARACTERS MAY BE USED.
CKSUM
-TWO ASCII hexadecimal characters representing an eight-bit checksum
formed by adding each byte of the string preceding the checksum into an
eight-bit accumulator and ignoring any overflow. The resulting eight-bit
sum is sent as two hexadecimal characters. The high order four bits are
the first characters and the low order four bits are the last character.
CKSUM is optional with the user.
CR
-Carriage Return
LF
-Line Feed
STATUS
-Two ASCII coded hexadecimal characters defining the system status.
DATA
-A string of ASCII digits, including minus sign where appropriate,
representing the numerical value of the PARAMETER specified. Limited to
four character spaces.
ECLIPSE INSTRUMENTATION DIVISION
page 3-1111
