QuickPak Pro Division By Zero

[Scott Slater]

QP Pro worked great on older PCs, but on newer faster PCs I have found that certain routines generate a division by zero error. The OpenCurtain function for one as well as any of the screen FX functions seem to have this problem. Any fixes or work-arounds?

-Scott

[Mike Doty]

[email protected] http://www.ethanwiner.com

Might make a difference if you originally purchased from him.
Wouldn't hurt going to the source. Say Happy New Years for me!

[Michael Mattias]

>Any fixes or work-arounds?

You can detect divide-by-zero exceptions inder Windows using Structured Exception Handling, but I don't know that would do you any good when it occurs in CMD.EXE running an MS-DOS program.

But maybe there is an interrupt generated on said error; if so, you could redirect that interrupt to your own handler and 'do something' with it at that time.

Haven't seen this "new fast PC generates divide-by-zero error" thing in eight or ten years now, but it used to be quite a common problem in the MS-DOS BASIC Usenet groups.

[Scott Slater]

It appears to be when the library is calculating delays (timers) internally. I have tried error trapping, but it won't pick it up since it is in the library itself. I also realized that the library shipped with source, so I am looking into it.

[Scott Slater]

It seems that the internal Pause functions are broken. They have a Div xxxx ASM location where they are calculating ms delays. I simply updated the unit code to use Delay Speed/1000 instead of PauseX Speed..., and it fixed that problem. I am sure that there are other parts of the library that use the internal Pause, but I haven't come across them yet.