Xylem SI Analytics TITRATOR TitroLine 7500 KF, Руководство по эксплуатации

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6 Data Communication via RS-232- and USB-B interface
6.1 General Information
The tirator TitroLine® 7500 KF trace has two serial RS-232-C interfaces to communicate data with other devices.
By means of these two interfaces it is possible to operate several devices on one computer (PC) interface.
In addition to that, the TitroLine® 7500 KF trace also has an alternatively USB-B interface, which can only be
used to connect a PC.
RS-232-C-1 establishes the connection to a connected computer or to the previous device of the “Daisy Chain“.
At the RS-232-C-2 it is possible to connect additional devices (Daisy Chain Concept).
PIN assignment of the RS-232-C interfaces:
6.2 Chaining multiple devices —“Daisy Chain Concept“
In order to activate several devices in a chain individually, each device must have an own device address. For
this it is at first necessary to establish a connection from the computer to the RS-232-C interface 1 of the first
devise in the chain by means of a RS-232-C data cable, e.g. Type No. TZ 3097. With the additional RS-232-C
data cable, Type No. TZ 3094, the RS-232-C- interface 2 of the first device is connected with the RS-232-C-
interface 1 of the second device. At interface 2 of the second device it is possible to connect an additional device.
The TitroLine® 7500 KF trace can also be connected via USB cable TZ 3840 (type A (M) – type B (M), 1.8m). It
is also possible to connect the TitroLine® 7500 KF trace via USB cable TZ 3840 (type A (M) --- USB type B (M),
1.8 m) to a USB interface of a PC. To accomplish this connection, a driver has to be installed on the PC. Then
the USB-B interface takes over the function of the RS232-1 interface.
The address always consists of two characters: e.g. address 1 of the two ASCII- characters <0> and <1>. The
addresses can be set from
00 to 15 , i.e. 16 possibilities. It must be ensured that the devices in a chain have
different addresses. If a device is addressed with its address, this device will process this command without
sending it to another device. The reply to the computer has also an own address. The addresses are allocated as
described in

Chapter 5.3 .
The burette TitroLine® 7500 KF trace receives commands from a PC at the interface 1 (USB- B) if the computer
knows the address. It also sends the answer via this interface. If the address of the incoming command does not
match the device address, the complete command will be forwarded to interface
2 . Interface 2 is connected to
interface 1 of another device. This device checks the address as well and reacts to the command as the first
TitroLine® 7500 KF trace did before.
All information (data strings) which arrive at interface 2 of the burette TitroLine® 7500 KF trace will immediately
be send to the computer via interface 1 (or USB-B interface). Thus, the computer receives the data of all devices.
In practice it is possible to connect up to 16 devices to one computer- (PC-) interface.
6.3 Instruction Set for RS-Communication
The commands consist of three parts: Address two-digit aa, e.g.: 01
Command e.g.: LR
Variable, if necessary e.g.: 14
and end of command <CR> <LF>
Every command must be completed with the ASCII - sign <CR> and <LF> (Carriage Return and Line Feed).
Only if the respective action has ended the answers will be returned to the computer.
Example: The command to send the results from the TitroLine® 7500 KF trace with the address 2.
The command consists of the characters: 02LR<CR LF>
In detail:
02 = Device address
LR = Load results
<CR LF> = Control character as command end
PIN-No. Meaning / Description
1 T x D Data output
2 R x D Data input
3 Digital mass