Humandata USB-402, Руководство пользователя

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9
USB-402 (Ver.1.0)
2.3. RS-485/422(4 wire) Mode
Item Specification Remarks
Comm. Method Full-duplex transmission
Baud Rate 300bps to 250Kbps Custom baud rate is supported
Number of Connectable
Terminals
128 Typical example
Terminal Resistor 120 Ω
Configurable by setting switch
(SWA1 - SWH1) ON/OFF
Transmit Enable
Control Automatically controlled by
USB controller
Receive Enable Control
Available by setting switch
(SWA2 - SWH2)
RS-485 or RS-422 mode can communicate with multiple terminals by using two twist
pair cables. Wires of upstream
and downstream are separated and simultaneous
communication (full-duplex transmission) is available.
2.4. RS-485(2 wire) Mode
Item Specification Remarks
Comm. Method Half-duplex transmission
Baud Rate 300bps to 250Kbps Custom baud rate is supported
Number of Connectable
Terminals
128 Typical example
Terminal Resistor 120 Ω
Configurable by setting switch
(SWA1 - SWH1) ON/OFF
Transmit-Receive
Switching Automatically controlled by
USB controller
Echo Cancellation
Available by setting switch
(SWA2 - SWH2)
RS-485 mode can communicate with multiple terminals by using a twist pair cable.