Dell Latitude XPi CD Reference Guide - Page 55

result when other programs require use of all or part of the memory already occupied by these TSR programs. Typically, your operating system's initialization or start-up files contain commands to start TSR programs when you boot your computer. If you suspect that one of these TSR programs is causing a memory conflict, remove the commands that start them from the start-up file. If the problem you were experiencing does not recur, one of the TSR programs probably created the conflict. Add the TSR commands back into the start-up files one at a time until you identify which TSR program is creating the conflict. Program Conflicts Some programs may leave portions of their setup information behind, even though you have exited from them. As a result, other programs cannot run. Rebooting your computer can confirm whether or not these programs are the cause of the problem. Other programs use specialized subroutines called device drivers that can cause problems in your computer. For example, a variation in the way the data is sent to an external monitor may require a special screen driver program that expects a certain kind of video mode or monitor. In such cases, you may have to develop an alternative method of running that particular program-the creation of a boot file made especially for that program, for example. For help with this situation, call the support service offered by the manufacturer of the software you are using. Avoiding Interrupt Assignment Conflicts Problems can arise if two devices attempt to use the same interrupt request (IRQ) line. To avoid this type of conflict, check the documentation for the default IRQ line setting for each installed device. Then consult Table 3-4 to configure the device for one of the available IRQ lines. NOTE: Installed devices cannot share the same COM port address. The default address of your computer's serial port is COM1. Table 3-4. IRQ Line Assignments IRQ Line Used/Available IRQ0 Generated by the system timer IRQ1 Generated by the keyboard controller to signal that the keyboard output buffer is full IRQ2 Generated internally by the interrupt controller to enable IRQ8 through IRQ15 IRQ3 Available for use by a PC Card unless the built-in serial port or infrared port is configured for COM2 IRQ4 Available for use by a PC Card unless the built-in serial port is configured for COM1 (the default) IRQ5 Available for use by the audio controller IRQ6 Generated by the diskette drive controller to indicate that the diskette drive requires the attention of the microprocessor IRQ7 Available for use by a PC Card or audio controller if the built-in parallel port is disabled IRQ8 Generated by the system I/O controller's RTC IRQ9 Available for use by the PC Card interrupt controller or the audio controller IRQ10 Available for use by a PC Card or audio controller unless the Advanced Port Replicator is attached IRQ11 Available for use by a PC Card unless the Advanced Port Replicator is attached NOTE: For the full name of an abbreviation or acronym used in this table, see the Glossary in the online System User's Guide. Troubleshooting Your Computer 3-15