Technical description – Impulse 7406 User Manual
Page 8
Technical Description
Sealevel Systems VERSA COMM+4.LPCI Page
6
Technical Description
The VERSA COMM+4.LPCI utilizes the 16C854 UART. This chip features programmable baud rate, data format,
interrupt control and a 128-byte input and output FIFO, and is functionally 4 16C850 UARTs.
Connector Pin Assignments
DB-25 Female (RS-232 DTE)
Signal Name
Pin
#
Mode
GND Ground
7
TD Transmit
Data
2
Output
RTS
Request To Send
4
Output
DTR
Data Terminal Ready
20
Output
RD Receive
Data
3
Input
CTS
Clear To Send
5
Input
DSR
Data Set Ready
6
Input
DCD
Data Carrier Detect
8
Input
RI Ring
Indicator
22
Input
DB-9 Male (EIA-574 DTE)
Signal Name
Pin
#
Mode
GND Ground
5
TD Transmit
Data
3
Output
RTS
Request To Send
7
Output
DTR
Data Terminal Ready
4
Output
RD Receive
Data
2
Input
CTS
Clear To Send
8
Input
DSR
Data Set Ready
6
Input
DCD
Data Carrier Detect
1
Input
RI Ring
Indicator
9
Input
Card Edge DB-44 Female
Port #
1
2
3
4
GND
17 21 24 28
RD 4
8
12
30
RI
33 37 41 44
DCD 3
7
11
15
DTR
32 36 40 43
RTS 2
6
10
14
DSR
31 35 39 42
TD 1
5
9
13
CTS
16 20 23 27
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.