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SC100 ISOLATED RS-232 BAUD RATE CONVERTER INTERFACE
The SC100 interface is an updated version of
the SC7638 interface. The device has signal
and power isolation and is powered by the
datalogger. A male 9 pin D-type connector on
one side connects to a CR10(X) or 21X, and a
female 9 pin D-type connector connects to an
RS232 device (computer or sensor (jumper
configurable DTE or DCE)). Features
programmed to this point include:
•
Burst mode: (from datalogger to computer)
In this mode the SC100 can receive burst
data from the datalogger at 76.8k baud,
then buffer the data and transmit to the
computer at 38.4k baud.
•
Instruction 15 mode: The SC100 can be
configured to support the datalogger
Instruction 15 as a transducer RS232
communication interface. The SC100
function is to insure data synchronization
and to support baud rates other than 300 or
1200 baud. In this mode the SC100 has a
configurable record structure which can be
initialized by the datalogger. This
configurable information is volatile and
requires re-initialization if the SC100 is
powered down. By default (without
datalogger initializing the SC100) the
SC100 simply buffers the data coming from
a sensor or computer until a carriage return,
then flags the datalogger that data is
present. The SC100 then transmits the
data to the datalogger when Instruction 15
asserts the DTR line. In a given record
structure, the SC100 searches for a
specified string then buffers all of the data
following the string until it encounters a
termination character (the search string and
termination characters are user specified
through the optional initialization sequence).
Some data conversion (e.g., alpha
characters to number equivalents) can also
be performed.
Command sequences from the datalogger
(CR10(X) only). This is the optional
initialization sequence.
Command for initializing search/find &
replace structure:
ctrl-Q(17), I (73), 1 (49)
Following these three command bytes the
SC100 will expect:
Structure initialization information:
1) search byte 1 (range from 1-127; must be 0
if not used)
2) search byte 2 (range from 1-127; must be 0
if not used)
3) search byte 3 (range from 1-127; must be 0
if not used)
4) search byte 4 (range from 1-127; must be 0
if not used)
5) search byte 5 (range from 1-127; must be 0
if not used)
6) search byte 6 (range from 1-127; must be 0
if not used)
7) byte --> 0 (this location must always be 0)
8) find and replace with 0 (range from 1-126;
must be 127 if not used )
9) find and replace with 1 (range from 1-126;
must be 127 if not used )
10) find and replace with 2 (range from 1-126;
must be 127 if not used )
11) find and replace with 3 (range from 1-126;
must be 127 if not used )
12) termination character (range from 1-127)
NOTE: Within the CR10(X) Instruction 15
parameter 06 (number of locations to send)
must be 15. Also parameter 03 (cts/delay
before send) must be 1.
