Troubleshooting - AT RS-232 or AT RS-485 Windows NT

The following is a standard troubleshooting procedure:

The serial configuration utility niports contains configuration information for serial hardware it is aware of that is installed in your system.

To start the configuration utility, select Start»Settings»Control Panel, and double-click on the niports icon.

If serial ports are missing from the list, follow these steps:
1. Make sure the hardware is installed.
2. Make sure you have installed the Microsoft PnP ISA Enabler driver. niports cannot recognize the AT boards without the Microsoft PnP ISA Enabler driver. For more information, refer to the Installation of isaPNP page.
Resource conflicts occur when your system contains hardware that is configured to use the same resources as your serial interface. The serial driver detects some resource conflicts when it loads. When the driver detects conflicts as it loads, it records an error message describing the conflict. You can use the Event Viewer to see which resource is in conflict. To run the Event Viewer, select Start»Programs»Administrative Tools»Event Viewer.

After you have identified the resource that caused the conflict, use the serial configuration utility, niports, to reconfigure your serial interface so that it uses conflict-free resources.

To help in the selection of conflict-free resources, Microsoft has provided a utility called Windows NT Diagnostics. This utility displays a list of the I/O port addresses, IRQ levels, and DMA channels that are currently being used in your system. Assign resources not listed by this utility to your serial interface.

To run the Windows NT Diagnostics, select Start»Programs»Administrative Tools»Windows NT Diagnostics.
This section lists possible diagnostic error messages, along with solutions:
- If the No National Instruments serial port found error message appears, refer to the verification instructions to follow these troubleshooting steps:
  1. Verify the hardware resources.
  2. Verify that the National Instruments serial driver is installed.
  3. If either the serial hardware or serial.sys file is missing, reinstall the hardware and software.
- If the utility reports fewer ports installed than it should, refer to the verification instructions to follow these troubleshooting steps:
  1. Verify the hardware resources.
  2. Verify that the National Instruments serial driver is installed.
  3. Check the hardware installation to make sure the correct number of boards/ports are installed.
- If the I/O address test failed, Interrupt test cannot be performed. error message appears, verify the hardware resources as described in the verify page. If the test still fails, you probably have an I/O address conflict with legacy boards in your system. Use the niports configuration utility to change the base I/O addresses assigned to your ports.
- If the Interrupt test failed error message appears, verify the hardware resources as described on the verify page. If the test still fails, you probably have an IRQ conflict with legacy boards in your system. Use the niports configuration utility to change the IRQ level assigned to your port.