101-0577 Rabbit Semiconductor, 101-0577 Datasheet - Page 35

• Manufacturer Part Number: 101-0577
• Description: KIT DEV FOR BL2500 COYOTE
• Manufacturer: Rabbit Semiconductor
• Series: Coyoter
• Type: Single Board Computers (SBC)r

Specifications of 101-0577

• Contents: SBC, Dev. Board, AC Adapter, Cable and Dynamic C® CD-ROM
• Product: Modules
• Data Bus Width: 10 bit
• Processor Type: Rabbit 3000
• Sram: 128 KB
• Flash: 256 KB
• Number Of I/os: 24
• Backup Battery: 3 V Lithium Coin Type
• Operating Voltage: 8 V to 40 V
• Power Consumption: 1 W
• Board Size: 100 mm x 100 mm x 29 mm
• Description/function: Computer Module
• Interface Type: Ethernet
• For Use With/related Products: BL2510
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

3.5.2 RS-485
The Coyote has one RS-485 serial channel, which is connected to the Rabbit 3000 Serial
Port D through an RS-485 transceiver. The half-duplex communication uses PA4 to con-
trol the transmit enable on the communication line. Using this scheme a strict master/slave
relationship must exist between devices to insure that no two devices attempt to drive the
bus simultaneously.
Serial Port D is configured in software for RS-485 as follows.
The configuration shown above is based on circular buffers. RS-485 configuration may
also be done using functions from the
The Coyote can be used in an RS-485 multidrop network spanning up to 1200 m (4000 ft),
and there can be as many as 32 attached devices. Connect the 485+ to 485+ and 485– to
485– using single twisted-pair wires as shown in Figure 15. Note that a common ground is
recommended.
User’s Manual
#define ser485open serDopen
#define ser485close serDclose
#define ser485wrFlush serDwrFlush
#define ser485rdFlush serDrdFlush
#define ser485putc serDputc
#define ser485getc serDgetc
#define DINBUFSIZE
#define DOUTBUFSIZE 15
#ifndef _485BAUD
#define _485BAUD 115200
#endif
Figure 15. Coyote Multidrop Network
15
PACKET.LIB
library.
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