CVW 3.05 Incompatible with Some VGA Video Systems

ID Number: Q73192

3.05

WINDOWS

buglist3.05

Summary:

Microsoft CodeView for Windows (CVW) version 3.05 may be incompatible

with some VGA video systems. The reported symptoms include screen

corruption and/or system hangs that may require a cold boot.

A possible workaround is to treat the system as if it has a

nonstandard VGA monitor.

More Information:

Single-monitor debugging of Windows applications was first made

possible with this version of CVW, and the majority of the reported

display problems have occurred when trying to access the application's

output screen while running on a single monitor. However, similar

problems may occur when using CVW version 3.05 in a dual-monitor

configuration.

Note: Some video problems in CVW may be the result of using special

VGA drivers. CVW is designed to work with the standard Windows VGA

driver (VGA.DRV). If you are experiencing CVW display problems, you

should first check that you have VGA.DRV installed.

If you are experiencing video problems while using VGA.DRV, you should

try working around them by setting up your system for non-VGA or

nonstandard VGA use by doing the following:

1. Place the following line in the [386enh] section of the SYSTEM.INI

file:

device=VCV.386

2. Place the VCV.386 driver in the WINDOWS directory (it is shipped

with CVW 3.05)

3. Always invoke CVW with /V. This is easily accomplished by placing

/V in the Command Line box of the File Properties for CVW.

This method is explained in the README.DOC that accompanies CVW

version 3.05 in a section referring to use of CVW with non-VGA

monitors.

The major disadvantage to using this method is that if the VCV.386

driver is used, the F4 key (view output screen) is not functional.

Whenever you return to Windows from CVW, all Windows applications

(including the one you are debugging) get a WM_PAINT message. This

makes debugging of paint code difficult (if not impossible) because

you cannot see what you are painting one step at a time. This is

usually accomplished by pressing F4 after executing the code being

tested to see if the output is correct. This also means that the paint

code must be relatively functional to debug at all.

The following VGA adapters are among those that have been reported to

have video problems with CVW version 3.05:

Diamond Speedstar version 3.23

Orchid Pro Designer 2 version 3.1

Vega VGA

ATI VGA Wonder

In some cases, it may help to obtain an updated video BIOS from the

video card manufacturer.

Microsoft has confirmed this to be a problem in CodeView for Windows

version 3.05. We are researching this problem and will post new

information here as it becomes available.