Dell 4100/180, 4100/200 Input Errors, Program Conflicts, Avoiding Interrupt Assignment Conflicts

Input Errors

If a specific key or set of keys is pressed at the wrong time, a program may give you unexpected results. See the documentation that came with the application program to make sure that the values or characters you are entering are valid.

Make sure that the operating environment is set up to accommodate the programs you use. Keep in mind that whenever you change the parameters of the computer’s operating environment, you may affect the successful operation of the programs. Sometimes, after modifying the operating environment, you may need to reinstall a program that no longer runs properly.

Program Conflicts

Some programs may leave portions of their setup infor- mation behind, even though you have exited from them. As a result, other programs cannot run. Rebooting the system can confirm whether or not these programs are the cause of the problem.

There are also programs that use specialized subroutines called device drivers that can also cause problems with the computer system. For example, a variation in the way the data is sent to the 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 alter- native method of running that particular program—the creation of a boot file made especially for that program, for example. Call the support service for the software you are using to help you with this problem.

Avoiding Interrupt Assignment Conflicts

Problems can arise if two devices attempt to use the same interrupt request (IRQ) line. To avoid this type of con- flict, check the documentation for the default IRQ line setting for each installed expansion card. Then consult Table 4-1 to configure the card for one of the available IRQ lines.

Table 4-1. Default IRQ Line Assignments

IRQ Line	Used/Available
IRQ0	Used by the system timer
IRQ1	Used by the keyboard to signal that
	the output buffer is full
IRQ2	Used by interrupt controller 1 to
	enable IRQ8 through IRQ15
IRQ3	Used by serial port 2
IRQ4	Used by serial port 1
IRQ5	Available
IRQ6	Used by the diskette/tape drive con-
	troller
IRQ7	Used by the parallel port
IRQ8	Used by the RTC
IRQ9	Available
IRQ10	Available
IRQ11	Available
IRQ12	Used by the mouse port
IRQ13	Used by the math coprocessor (if
	applicable)
IRQ14	Available
IRQ15	Available

NOTE: For the full name of an abbreviation or acronym used in this table, see the abbreviation and acronym list.

4-2 Dell PowerEdge 4100/180 and 4100/200 Systems Installation and Troubleshooting Guide