[comp.sys.ibm.pc.misc] INT 8 isn't a timer interrupt in real-mode on a 386 ?

rhl@cf-cm.computing-maths.cardiff.ac.uk (Robert Hartill) (03/07/91)

i've written a real-mode executive i.e a small OS for a PC,
i want to use INTerrupt 8 to invoke my scheduler,

When i run my executive under the Turbo Debugger (TD and TD386) INT 8
behaves as expected, and my scheduler is invoked,

When i run my executive from the dos command line, the scheduler never
gets invoked,

According to the books i've read,, INT 8 is a timer in real mode,
and a 'double fault' (if i remember correctly) exception in protected mode

A can't be accidentally changing into protected mode, that takes a bit
of code to do the initialisation (yes ?)

HELP !!!

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::     Robert Hartill, Dept Of Computing Mathematics, UWCC, Cardiff, UK.     ::
::          e-mail : rhl@cm.cf.ac.uk         Fax : 0222 371921               ::
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There are two kinds of people in the world: those who believe there are two
 kinds of people in the world, and those who don't.   - Ross F. Papprill.
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