Auto-RTS Transceiver Control
In Windows applications the driver must be enabled and disabled as needed, allowing all cards to share
a two-wire or four-wire cable. This card controls the driver automatically. With automatic control, the
driver is enabled when data are ready to be transmitted. The driver remains enabled for the
transmission time of one additional character after data transfer is complete and then is disabled. The
receiver is normally enabled but is disabled during transmission and then re-enabled after transmission
is completed. The card automatically adjusts its timing to the baud rate of the data.
Specifications
Communications Interface
•
I/O Connection:
Shielded male D-sub 9-pin IBM AT style connector compatible with
RS422 and RS485 specifications.
•
Character length:
5, 6, 7, or 8 bits.
•
Parity:
Even, odd or none.
•
Stop Interval:
1, 1.5, or 2 bits.
•
Serial Data Rates:
Up to 115,200 baud, Asynchronous. Faster rates, up to 460,800 baud,
are achieved by jumper selection on the card. Type 16550 buffered
UART.
RS422/RS485 Differential Communication Mode
•
Receiver Input Sensitivity:
+200 mV, differential input.
•
Common Mode Rejection:
+12V to -7V
•
Drive Capability:
60 mA transmit output with thermal shutdown.
•
Multipoint:
Compatible with RS422 and RS485 specifications.
Note
Up to 32 drivers and receivers allowed on line. Serial communications ACE used is type 16550.
Driver/Receivers used are type 75ALS176.
Environmental
•
Operating Temperature Range: 0 to +60 °C
•
Humidity:
5% to 95%, non-condensing.
•
Storage Temperature Range: -50 to +120 °C
•
Size:
4.80" long (122mm) by 1.80" high (46 mm).
•
Power Required:
+5VDC at 175 mA typical
Manual PCI-COM-1S
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