Serial Port

Putting Serial-Port Technology in Perspective, Part 1
Putting Serial-Port Technology in Perspective, Part 2

RS-232 / RS-422 / RS-485 Comparison

Serial Port Controller from HITR

Serial Port Pinout
   DB9 Connector
   DB25 Connector
95A Serial Ports
Serial ADF


Serial Port Pinout

DB9 Connector

Pin Signal
1 Data Carrier Detect
2 Receive Data
3 Transmit Data
4 Data Terminal Ready
5 Signal Ground
6 Data Set Ready
7 Request To Send
8 Clear To Send
9 Ring Indicator

DB25 Connector

Pin Signal Pin Signal
1 N/C 14 N/C
2 Transmit Data 15 N/C
3 Receive Data 16 N/C
4 Request To Send 17 N/C
5 Clear To Send 18 N/C
6 Data Set Ready 19 N/C
7 Signal Ground 20 Data Terminal Ready
8 Data Carrier Detect 21 N/C
9 N/C 22 Ring Indicator
10 N/C 23 N/C
11 N/C 24 N/C
12 Reserved 25 N/C
13 N/C


95A Serial Ports

   Serial Port A can be used to remote start your system. Go to JMP4 to get more info...  To add more serial devices to your server, you can install serial adapters in the expansion slots, and then attach the devices to the connectors on the adapters.  In some specialized cases, an ASCII display station can be attached to a serial connector (see ASCII Display Stations).
   The system board provides two 9-pin D-shell connectors to the serial port controllers on the system board. The serial ports do not support current loop.

95A Serial ports use the National Semiconductor's DS75154 Quad Line Receiver.


Serial ADF

Note: Not all choices may be available or appear in the same order on different systems. 

First Serial Port (A)
   The serial port connector can be assigned as Serial 1 through Serial 16, or disabled.  Standard usage of interrupt levels is IRQ 4 for serial 1 and IRQ 3 for any other serial level. 
      <SERIAL 1, IRQ 4 (io 03f8h-03ffh 83f8h-83ffh 4620h-4620h int 4)>, 2, 3 (02f8-02ff 82f8-82ff 4621-4621 int 3), 3, 3 (3220-3227 0b220-0b227 4622-4622 int 3),  4, 3 (3228-322f 0b228-0b22f 4623-4623 int 3), 5, 3 (4220-4227 0c220-0c227 4624-4624 int 3), 6, 3 (4228-422f 0c228-0c22f 4625-4625 int 3), 7, 3 (5220-5227 0d220-0d227 4626-4626 int 3), 8, 3 (5228-522f 0d228-0d22f 4627-4627 int 3), 9, 3 (3a20-3a27 0ba20-0ba27 4628-4628 int 3), 10, 3 (3a28-3a2f 0ba28-0ba2f 4629-4629 int 3), 11, 3 (3a30-3a37 0ba30-0ba37 462a-462a int 3), 12, 3 (3a38-3a3f 0ba38-0ba3f 462b-462b int 3), 13, 3 (3a80-3a87 0ba80-0ba87 462c-462c int 3), 14,  3 (3a88-3a8f 0ba88-0ba8f 462d-462d int 3), 15, 3 (3a90-3a97 0ba90-0ba97 462e-462e int 3), 16, 3 (3a98-3a9f 0ba98-0ba9f 462f-462f int 3), "SERIAL 4, IRQ 4, CUSTOM (3228-322f 0b228-0b22f 4623-4623 int 4), 5, 4 (4220-4227 0c220-0c227 4624-4624 int 4), 6, 4, 
(4228-422f 0c228-0c22f 4625-4625 int 4), 7, 4 (5220-5227 0d220-0d227 4626-4626 int 4), 8, 4 (5228-522f 0d228-0d22f 4627-4627 int 4), 9, 4 (3a20-3a27 0ba20-0ba27 4628-4628 int 4), 10, 4 (3a28-3a2f 0ba28-0ba2f 4629-4629 int 4), 11, 4 (3a30-3a37 0ba30-0ba37 462a-462a int 4), 12, 4  (3a38-3a3f 0ba38-0ba3f 462b-462b int 4), 13,  4 (3a80-3a87 0ba80-0ba87 462c-462c int 4), 14, 4 (3a88-3a8f 0ba88-0ba8f 462d-462d int 4), 15, 4 (3a90-3a97 0ba90-0ba97 462e-462e int 4), 16, 4 (3a98-3a9f 0ba98-0ba9f 462f-462f int 4), Disabled 

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