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Technical Description
Technical Description
The COMHP 7801 utilizes the 16C554 UART. This chip features
programmable baud rate, data format, interrupt control and a 16-byte input and
output FIFO, and is functionally 4 16C550 UARTs. A full array of advanced
UARTS is also available for this card. Contact CyberResearch for more
information.
Connector Pin Assignments
DB-25 (RS-232 DTE)
Signal
GND
TD
RTS
DTR
RD
CTS
DSR
DCD
RI
Name
Ground
Transmit Data
Request To Send
Data Terminal Ready
Receive Data
Clear To Send
Data Set Ready
Data Carrier Detect
Ring Indicator
DB-9 (EIA-574 DTE)
Signal
GND
TD
RTS
DTR
RD
CTS
DSR
DCD
RI
(DB25 MALE)
Pin #
7
2
4
20
3
5
6
8
22
Mode
Output
Output
Output
Input
Input
Input
Input
Input
(DB9 MALE)
Name
Ground
Transmit Data
Request To Send
Data Terminal Ready
Receive Data
Clear To Send
Data Set Ready
Data Carrier Detect
Ring Indicator
Pin #
5
3
7
4
2
8
6
1
9
Mode
Output
Output
Output
Input
Input
Input
Input
Input
Technical Note: Please terminate any control signals that are not going to be
used. The most common way to do this is connect RTS to CTS and RI. Also,
connect DCD to DTR and DSR. Terminating these pins, if not used, will help
insure
you
get
the
best
performance
from
your
adapter.
CyberResearch COMHP 7801
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