Datalogic DP1200, Руководство по установке

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DP1200
16
2
The user can assign an address to the device for RS485 Half-Duplex Multidrop
applications, by using the two rotary switches S1 and S2, placed on the right side of
the board: S1 defines the Tens, S2 defines the Units.
In Multiplexer applications this address is in the range 00 - 31; in RS485
Master/Slave applications the address is in the range 00 - 04.
The address can also be assigned through WinHost. In this case the rotary switches
have no effect.
0 0
Tens Units
OFF
ON
S1 S2
S4
Figure 14 - Address selection and bus termination
The switch S4 enables or disables the insertion of the bus termination resistor for
RS485 Half-Duplex Multidrop applications.
CAUTION
In Multiplexer applications the termination resistor must be enabled
ONLY on the last device of the chain, the farthest away from the
Multiplexer (assuming the Multiplexer is the first device of the
chain). On all the other devices this resistor MUST NOT be enabled
(S4 = OFF).
Normally it is not necessary to enable the termination resistor (S4
always OFF); it is suggested only in applications where the
communication speed or the bus length are critical parameters.