User Manual
 Card Setup 
Sealevel Systems ULTRA-485 Page 7 
Connector Pin Assignments 
EIA-530 
DIP-shunt E4 selects the pin out for the DB-25 connector P3. With the 5 
position shunt in the EIA-530 mode, the ULTRA 485 complies with the EIA-
530 pin out with the following signals supported: 
EIA-530
E4
SIO-485 
Figure 6 - DIP-shunt E4 (EIA-530 Mode) 
Signal  Name  Pin # Mode 
GND  Ground  7   
RDB  RX+  Receive Positive  16  Input 
RDA  RX-  Receive Negative  3  Input 
CTSB  CTS+  Clear To Send Positive  13  Input 
CTSA  CTS-  Clear To Send Negative  5  Input 
DSRB  DSR+  Data Set Ready Positive  22  Input 
DSRA  DSR-  Data Set Ready Negative  6  Input 
DCDB  DCD+  Data Carrier Detect Positive  10  Input 
DCDA  DCD-  Data Carrier Detect Negative  8  Input 
TDB  TX+  Transmit Positive  14  Output 
TDA  TX-  Transmit Negative  2  Output 
RTSB  RTS+  Request To Send Positive  19  Output 
RTSA  RTS-  Request To Send Negative  4  Output 
DTRB  DTR+  Data Terminal. Ready Positive  23  Output 
DTRA  DTR-  Data Terminal Ready Negative  20  Output 










