101-0394 Rabbit Semiconductor, 101-0394 Datasheet - Page 32

• Manufacturer Part Number: 101-0394
• Description: CARD D/A +/-10V SR9410 SMARTSTAR
• Manufacturer: Rabbit Semiconductor

Specifications of 101-0394

• Accessory Type: Smart Star D/A Card
• For Use With/related Products: SR9410
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

3.2 Smart Star CPU Card Features
3.2.1 Serial Communication
The CPU Card has one screw terminal header for RS-232/RS-485 serial communication
(J3) and one RJ-45 Ethernet jack (J7, SR9150 only). The RJ-12 jack, J6, is reserved for
future use and therefore has no signals. The pinouts are shown in Figure 10.
FD
Figure 10. Smart Star CPU Card Serial Pinout
The factory default for the CPU Card is one RS-232 (3-wire) and one RS-485 serial chan-
nel, corresponding to Mode 0 in Figure 10. The other modes shown in Figure 10 are set in
software via the Dynamic C serMode function call (see Section 4.5, “Serial Communica-
tion Calls”).
3.2.1.1 RS-232
The CPU Card’s RS-232 serial channel is connected to an RS-232 transceiver. The trans-
ceiver provides the voltage output, slew rate, and input voltage immunity required to meet
the RS-232 serial communication protocol. Basically, the chip translates the Rabbit 2000’s
0 V to +Vcc signals to RS-232 signal levels. Note that the polarity is reversed in an
RS-232 circuit so that +5 V is output as approximately -10 V and 0 V is output as approx-
imately +10 V. The transceiver also provides the proper line loading for reliable communi-
cation.
The maximum baud rate is 115,200 bps. RS-232 can be used effectively at this baud rate
for distances up to 15 m.
The Rabbit 2000 serial port C TXD and RXD signals are presented either as RS-232 TX
and RX or as RTS/CTS handshaking, depending on the mode selected with the Dynamic C
function serMode . The RS-232 signals are available on screw terminal header J3.
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Smart Star (SR9000)