Force Computers SPARC CPU-54, Справочное руководство

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Controls, Indicators, and Connectors Front Panel of the SPARC/CPU-54
SPARC/CPU-54 3 - 7
Serial I/O
The serial interface on the CPU board’s front panel holds the signals for
the two serial interfaces A and B. If you want to use both interfaces you
need a splitter cable.
Both serial I/O interfaces of the CPU board are independent full-duplex
channels. For each of them, the four signals RXD, TXD, RTS, and CTS
are also provided via the respective VMEbus P2 connector.
Both I/O interfaces can be configured as RS-232 and RS-422. The selec-
tion is made via the switches SW7-1 and SW7-2.
Note: When configuring the serial interfaces as RS-422 and you want
to terminate the signals RxD+/- and CTS+/-, you have to mount termi-
nation resistors into the serial cable you use. These resistors are not
assembled on the CPU board.
The following figures show the pinout of the 26-pin connector in RS-232
and RS-422 mode (factory option).
Figure 11: Serial A+B Connector Pinout RS-232
Figure 12: 26-Pin Serial A+B Connector Pinout RS-422