Data Communication Via Rs-232- And Usb-B Interface; General Information; Meaning / Description; Chaining Multiple Devices -"Daisy Chain Concept - SI Analytics TitroLine 6000 Mode D'emploi

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6 Data Communication via RS-232- and USB-B interface

6.1 General Information

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The burette TitroLine
means of these two interfaces it is possible to operate several devices on one computer (PC) interface.
In addition to that, the TitroLine
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.
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The TitroLine 6000/7000 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
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.
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The burette TitroLine
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
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TitroLine 6000/7000 did before.
All information (data strings) which arrive at interface 2 of the burette TitroLine
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
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 dose 12.5 ml shall be sent to the burette TitroLine
The command consists of the characters: 02DA12.5<CR LF>
In detail: 02
DA
12.5
<CR LF> = Control character as command end
Chapter 6 Data Communication via RS-232 and USB-B interface
6000/7000 has two serial RS-232-C interfaces to communicate data with other devices. By
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6000/7000 also has an alternatively USB-B interface, which can only be used to
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6000/7000 via USB cable TZ 3840 (type A (M) --- USB type B (M), 1.8 m)
6000/7000 receives commands from a PC at the interface 1 (USB- B) if the computer
Command
Variable, if necessary
and end of command
= Device address
= Dosage command with filling and zero points of the display
= Volume in ml to be dosed
PIN-No. Meaning / Description
1 T x D Data output
2 R x D Data input
3 Digital mass
two-digit aa, e.g.: 01
e.g.: DA
e.g.: 14
<CR> <LF>
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6000/7000 will immediately be
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6000/7000 with the address 2.