Solution:

How to setup and test serial port for Windows 95/NT? For Windows 95 1. [Start] -> [Setup] -> [Control Panel] -> [Add New Hardware] 2. Click [Next], choose [N]ot to do auto search new hardware. 3. Click [Next], choose [Connection Port (COM & LPT)] Hardware Type. 4. Click [Next], select [Standard Connection Port Type] for manufacurer and [Communication Connection Port] for model. 5. Click [Next], then the default IRQ and IO Address will be shown. Click [Done]. Up to this point you have added a port to system without correct IRQ and IO settings. You can repeat step 1 to step 5 to add as many ports as you want (Max. 128 port). 6. [Control Panel] -> [System] -> [Device Manager] 7. Select your new COM?, then [Resource] 8. Select the ??? as [Basic Configure 8]. 9. Double click on IRQ to type in (select) the hardware IRQ, then [OK] 10. Double click on I/O rage to type in (select) the hardware I/O, then [OK]. Repeat step 6 to step 10 to setup each port correctly. 11. Click [OK] 12. Restart Windows 95 For Windows NT Similar to Windows 95. You add new serial port in the Control Panel. How to test serial port under Windows 95/NT? We use COMTEST.EXE undor DOS environment. For Windows 95/NT, there is a HyperTerminal (HyperTrm.EXE) for serial port testing. Because Windows 95 can only identify COM1, COM2, COM3 and COM4. If you have more than 4 serial port, you have to change the COM3, COM4 configuraion for testing each port. 1. Setup two serial port (A and B) 2. Prepare the connection cable to connect A and B. 3. Setup two HyperTerminal instance for the above serial port. (One for port A, one for port B) 4. Type some character for the first program instance (for port A), see the result on the other program instance (for port B). 5. Change the direction and test again.