Xerox -07W & -11W Printer User Manual


 
A-4
Troubleshooting
2. Some overruns are caused by SMARTDRV write caching. To dis-
able write caching but continue read caching, specify the drive letter
without a + or -. For example, SMARTDRV C enables read caching
but disables write caching. Note, however, that this will slow the PC
down.
3. Remove the DOS=HIGH statement from CONFIG.SYS as it causes
interrupts to be delayed longer. Note that this will take up precious
CONVENTIONAL memory space.
4. An ill-behaved TSR may be contributing to the problem. If so, try to
isolate it by removing all TSRs then adding them back one at a time.
5. Run in standard mode. Windows stops virtualizing I/O and there is
less overhead.
6. Remove the SOUNDS.DRV driver (which enables a variety of
sounds from your PC speaker) if it is present, as this disables inter-
rupts while activated.
Other things you could try are listed below.
Check that you are using the Windows versions of EMM386,
HIMEM.SYS and SMARTDRV, and not the DOS versions.
Don't run multiple disk-caching programs.
In CONFIG.SYS, set FILES to 30 or higher.
Check that you have SHELL=COMMAND.COM / E:2048 /P i.e.
2K environment.
If Windows hangs, increase the stacks to 64,512. The recommenda-
tion is 0,0.
Check that your TEMP variable points to a subdirectory that actually
exists and that there are at least 2 megabytes free on the disk.
Check that EMMExclude=A000-EFFF, otherwise Windows will
interfere with (DOS) high memory when it shouldn't.
For bizarre problems, disable shadow RAM. If this rectifies the prob-
lem, upgrade your BIOS.
Disable hardware cache in caching disk controller.
If you are using V3.1 of Windows communication drivers then try
using a serial port with a 16550 UART.
Note: Microsoft has produced a document called CE_OVERRUN
Errors with Serial Communications which can be obtained
by contacting Microsoft and asking for document number
Q79988.