-37-
17.5 The DE-2500 system uses a simple ASCII command to read the data collected. The ASCII
command must be transmitted to the controller by the PC or PLC before it can respond. The
command is shown below. The hexadecimal values for the characters are shown only for
those using low level (assembly language) decoding and will not appear on the
communications terminal screen.
ASCII >(01 DL 001)
HEX 3Eh 28h 30h 32h 20h 44h 4Ch 20h 30h 30h 32h 29h
COMMAND HEADER “>” (3Eh) - The command must begin with the command header.
START OF TEXT “(“ (28h) - The start of text character must be next.
NODE NUMBER 01 - 99 - The node number or address of the controller being contacted is
next. This number is programmed by the terminal program and can be viewed or edited in
the menu screen. A two digit number from 01 to 99 can be used.
SPACE (20h) - Following the node number is an ASCII space character (not printable, value
20h) to act as a delimiter between the node number and the two character command word.
COMMAND WORD “DL” (44h, 4Ch) - The command is an upper case DL for data log.
SPACE (20h) - A space again is used as a delimiter.
RECORD NUMBER 001 - 100 - The record number is the requested record. This number
can be any number from 001 to 100. Record number 001 always contains the most recent
record, 002 the second most recent and so on. The controller holds a maximum of 100
records in its memory before overwriting the oldest record.
END OF TEXT “)” (29h) - The end of text completes the message.
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