Dell Latitude CP Reference And Troubleshooting Manual

Also see for Latitude CP: Service manual Service manual

Contents

3-14 Dell Latitude CP Reference and Troubleshooting Guidecommands that start them from the start-up file. If theproblem you were experiencing does not recur, one of theTSR programs probably created the conflict. Add the TSRcommands back into the start-up files one at a time untilyou identify which TSR program is creating the conflict.Program ConflictsSome 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 yourcomputer can confirm whether or not these programs arethe cause of the problem.Other programs use specialized subroutines called devicedrivers that can cause problems in your computer. For exam-ple, a variation in the way the data is sent to an externalmonitor may require a special screen driver program thatexpects a certain kind of video mode or monitor. In such cases,you may have to develop an alternative method of running thatparticular program—the creation of a boot file made especiallyfor that program, for example. For help with this situation, callthe support service offered by the manufacturer of the softwareyou are using.Avoiding Interrupt Assignment ConflictsProblems can arise if two devices attempt to use the sameinterrupt request (IRQ) line. To avoid this type of con-flict, check the documentation for the default IRQ linesetting for each installed device. Then consult Table 3-4to configure the device for one of the available IRQ lines.NOTES: Installed devices cannot share the same COMport address. The default address of your computer’sserial port is COM1.To view IRQ line assignments in the Windows 95 operat-ing system, select the Start button, and point to Settingsand then to Control Panel. Double-click the System icon.Select the Device Manager tab, and then double-clickComputer.Table 3-4. IRQ Line AssignmentsIRQ Line Reserved/AvailableIRQ0 Reserved; generated by the system timerIRQ1 Reserved; generated by the keyboard con-troller to signal that the keyboard outputbuffer is fullIRQ2 Reserved; generated internally by theinterrupt controller to enable IRQ8through IRQ15IRQ3 Available for use by a PC Card unless thebuilt-in serial port or infrared port is con-figured for COM2 or COM4IRQ4 Available for use by a PC Card unless thebuilt-in serial port or infrared port is con-figured for COM1 (the default) or COM3IRQ5 Generated by the audio controllerIRQ6 Generated by the diskette drive controllerto indicate that the diskette drive requiresthe attention of the microprocessorIRQ7 Available for use by a PC Card or audiocontroller if the parallel port is disabledIRQ8 Reserved; generated by the system I/Ocontroller’s RTCIRQ9 Reserved; generated by the video controllerIRQ10 Available for use by a PC Card or audiocontroller unless the C/Port Advanced PortReplicator (APR) or C/Dock ExpansionStation is attachedIRQ11 Generated by the USB and PC Card con-trollers; available for use by a PC CardIRQ12 Reserved; generated by the keyboard con-troller to indicate that the output buffer ofthe touch pad or external PS/2 mouse is fullIRQ13 Reserved; generated by the math copro-cessorNOTE: For the full name of an abbreviation or acronym used inthis table, see the Glossary in the online System User’s Guide.