Delta OHM HD2205.2, Manual

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S
ERIAL
I
NTERFACE AND
USB
All instruments are fitted with an electrically isolated RS-232C serial interface, and an USB 2.0 in-
terface. Optionally, they can be connected using a serial cable with sub D 9-pole female connectors
(code
9CPRS232 ) and a cable with USB 2.0 connectors (code CP22 ).
The USB connection requires the previous installation of a driver in the instrument software.
Install
the driver before connecting the USB cable to the PC (please see the details on page 46).
Standard parameters of the instrument serial transmission are:
•
Baud rate 38400 baud
•
Parity None
•
N. bit 8
•
Stop bit 1
•
Protocol Xon/Xoff
It is possible to change the RS232C serial port baud rate by setting the "
Selection of the serial
transmission speed (Baud Rate) " parameter in the menu (please see page 18). The possible values
are: 115200, 38400, 19200, 9600, 4800, 2400, 1200. The other transmission parameters are fixed.
The USB 2.0 connection does not require the setting of parameters.
The selection of the port is carried out directly by the instrument: if the USB port is connected
to a PC, the RS232 serial port is automatically disabled.
All the commands transferred to the instrument must have the following structure:
XXCR where: XX is the command code and CR is the Carriage Return (ASCII 0D)
The XX command characters are exclusively upper case characters. Once a correct command is en-
tered, the instrument responds with "&"; when any wrong combination of characters is entered, the
instrument responds with "?".
The instrument response strings end with the sending of the CR (Carriage Return) and LF (Line
Feed) command, preceded by the “|” character, that is, the combination “|CRLF”.
Before sending commands to the instrument via the serial port, locking the keyboard to avoid func-
tioning conflicts is recommended: use the P0 command. When complete, restore the keyboard with
the P1 command.
COMMAND ACTION RESPONSE NOTES
AA Model request
HD2256-2
pH/chi/temperature
HD2205.2 = two pH channels
HD2206.2 = conductivity
HD2256.2 = pH+conductivity
AG Firmware version Firmware 1.00.100
AH Firmware date 2006_01_31
AS Serial number Ser. Number=00000000
AU User identification
User=FACTORY
User=Administrator
User=User_1
User=User_2
User=User_3
User=Anonymous