7
Click the OK button to run the program.
3. With the TTY program running, select Settings from the menu.
Select the COM port number that has the loopback plug on it.
Uncheck all of the flow control checkboxes (DTR/DSR, RTS/CTS, XON/XOFF).
Click OK.
From the TTY Main menu select Action, then Connect.
4. At this point you should get a blinking cursor in the upper left corner (under the menu bar).
5. You should be able to type on the keyboard and see the letters that you type on the screen. If you see what
you are typing, then your port is installed and operating properly.
If you do not get to the blinking cursor stage, but rather encounter a “Connection Failed” message box, some
possible causes are:
1. In NT, if multiple ports are opened (running more than one instance of TTY), the ports are using the same
IRQ, and the PermitShare registry entry is 0, the second port to be opened will fail. Use the registry
editor and expand HKEY_LOCAL_MACHINE ->SYSTEM ->CurrentControlSet ->Services ->Serial,
change the PermitShare value from 0 to 1, reboot, and run the test again.
2. The interrupt that was selected by the plug-and-play bios is trying to be shared with another device that is
not configured to share the IRQ (either Device or Driver Exclusive IRQ setting). Try a different PCI slot or
disable the other offending device.
3. IRQ steering is enabled on Windows 98 and Windows is not assigning an IRQ to the Fastcom card. Try
disabling IRQ steering or varying the options in Control Panel ->System ->Device Manager ->System
Devices ->PCI Bus.
4. Multiple COMx assignments. In Windows NT, the driver setup assumes that there are not any ports
installed above COM4, and starts assigning the Fastcom ports at COM5. If there is already a COM5 (or
higher) in the system, it is likely that the Fastcom ports are being assigned to the same port name(s).
Run the SERIALGT.EXE program (D:\Fastcom_disks\AsyncPCI\nt\serialgt.exe for Windows NT,
D:\Fastcom_disks\AsyncPCI\95\serialgt.exe for Windows95) and re-assign the com port numbers to these
ports to be different than any other ports in the system.
If you get to the blinking cursor stage, but do not see what you type with the loopback installed, some possible
reasons are:
1. Incorrect/faulty loopback construction or a bad connection.
2. The port is setup to have RS-485 enabled and the “RX Echo Disable” checkbox is checked. If the RX
Echo Disable is checked you will be unable to run a simple loopback test, as the purpose of the echo
disable is to strip the characters that are sent/received at the same time. Uncheck the RX Echo disable,
reboot, and try the test again.
3. The RTS/CTS flow control is checked and there is not a RTS->CTS loopback or the CTS disabled
checkbox was unchecked. If you enable flow control, you must allow CTS to be active in order for the
driver to transmit data. Either disable flow control or wire the RTS->CTS (and possibly DTR->DSR) loops
and try the test again.
4. The loopback plug is not on the correct port/cable.