101-0506 Rabbit Semiconductor, 101-0506 Datasheet - Page 33

• Manufacturer Part Number: 101-0506
• Description: CARD CPU SR9160 128K SRAM SMRTST
• Manufacturer: Rabbit Semiconductor

Specifications of 101-0506

• Accessory Type: Smart Star CPU Card
• For Use With/related Products: SR9160
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

3.2.1.2 RS-485
The CPU Card has one RS-485 serial channel, which is connected to the Rabbit 2000
serial port C through an RS-485 transceiver. The chip’s slew rate limiters provide for a
maximum baud rate of 250,000 bps, and allows networking over a distance of up to 300 m
(or 1000 ft.). The half-duplex communication uses the Rabbit 2000’s PD4 pin to control
the data enable on the communication line.
The RS-485 signals are available on the CPU Card through screw terminal header J3.
The Smart Star control system can be used in an RS-485 multidrop network. Connect the
485+ to 485+ and 485– to 485– using single twisted-pair wires on the CPU Card’s header
J4 as shown in Figure 11. Note that a common ground is recommended.
Figure 11. Multidrop Smart Star Network
User’s Manual
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