Associated Research HYPOTULTRA III 7620, Руководство по эксплуатации и обслуживанию

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serial port can be set to RS232, RS485, or OFF.
RS232 Interface
When selecting RS232, the protocol for interfacing and communicating with a PC can be
found in section 8.8. RS232 Interface of this manual.
RS485 Interface
The RS485 interface of the Data Storage Card is designed to function on a two-wire (half-
duplex) RS485 network, i.e. data is received and transmitted differentially on the same pair
of wires. The RS485 cabling should be configured as shown:
The wire used to connect the DATA signals from the Data Storage Card to the RS-485
network should be twisted pair.
Before sending a command to the RS485 enabled Data Storage Card, the unit that the
command is intended for needs to be addressed. To send the address, the following
format is used:
X <RS485 Address><line feed>
Note that there should be a character space between “X” and the RS485 address. After
addressing the unit, the command can be sent. The instrument that was last addressed will
receive all subsequent commands sent on the data bus. If the RS485 address specified is
“0”, then all RS485 instruments on the bus will receive the command. The command set
used for RS485 is the same as the command set for RS232. See section 8.8 for the RS232
command set.
When using the RS485 bus and sending the “0” address, the instruments will not respond
with the Acknowledge (06H or 6 decimal) or Not Acknowledge (15H or 21 decimal)
strings after a command is sent, and will not respond to any Query Commands.
It is also possible to combine the RS485 address and the desired instrument command all
in the same string using the following format:
X <RS485 Address>;<Command><line feed>
Note: When communicating with the HypotULTRA III using the RS485/RS232 port,
results are not saved to the Data Storage Card.
Data Card Serial Port PC / Bus Controller
6
8
5
DATA +
DATA -
DATA +
DATA -
GND
GND