AR 350AH1A, Руководство по эксплуатации и обслуживанию

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Model 350AH1A
16 Rev B
2.6.2 RS-232 Communications
The RS-232 port is a serial communications bus. All commands and queries through this port must be
terminated with a Line Feed character. When a valid query is received, it is processed and the result is
immediately transmitted back over the RS-232 interface. This port is designed to time-out if there is no
activity on the bus for more than 5 seconds. At this time, the internal buffer is cleared and a
TIMEOUT_ERROR message followed by a Line Feed character is sent out from this port.
The baud rate for the RS-232 port is user selectable from the RS-232/Fiber-Optic Serial Baud Rate selection
screen. To get there from the Main Menu, touch the User menu button followed by the I/O menu button and
finally the Serial menu button. A thin black outline indicates the present baud rate selection. When the back
button is pushed the baud rate selection is stored to non-volatile memory. Therefore, if power is lost prior to
hitting the back button, any baud rate selection changes will be lost. The default baud rate is 19200.
NOTE: This baud rate setting is shared by both the RS-232 port and the Fiber-Optic serial port.
The RS-232 port is setup as a Data Circuit-terminating Equipment (DCE) port. When connecting to a
Personal Computer (PC) a straight one-to-one cable should be used. A null modem is NOT needed. The
settings and pinout diagram for this port can be found below.
Table 2-2. RS-232 Port Settings
Word Length 8 bits
Stop Bits: 1
Baud Rate: User selectable (default is 19200)
Parity: None
HW Handshake: None
Table 2-3. RS-232 (DCE) Port Pinout Diagram DB-9 Female
Pin 1 DCD
Pin 2 TD
Pin 3 RD
Pin 4 DTR
Pin 5 GND
Pin 6 DCR
Pin 7 CTS
Pin 8 RTS
Pin 9 Unused
2.6.3 Fiber-Optic Serial Communications
The Fiber-Optic port is a serial communications bus. All commands and queries through this port must be
terminated with a Line Feed character. When a valid query is received, it is processed and the result is
immediately transmitted back over the Fiber-Optic interface. This port is designed to time-out if there is no
activity on the bus for more than 5 seconds. At this time, the internal buffer is cleared and a
TIMEOUT_ERROR message followed by a Line Feed is sent out from this port.