Re: LF: Hooking parallel port interrupt.


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Re: LF: Hooking parallel port interrupt.



At 05:35 PM 11/22/96 -0800, you wrote:
>Help: I am writing a program in c++ for my parallel link cable. anyways,
>what interrupt should i hook in order to intercept calls to lpt2? my book
>said 0x0d but that didn't work. is there something else i have to do?


First of all, the parallel port is usually on IRQ 7, which means that the
interrupt to hook is 0xF. Secondly, with the homemade parallel cable, there
is no point in hooking the interrupt; it is triggered when pin 10 has an
edge condition (goes from HI to LO or vice versa). Pin 10 is not connected
to anything in the homemade parallel link, so the IRQ would never be
triggered. 


Without hardware modifications to the cable, the parallel interrupt is
useless. You will have to use polling.




<pre>
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David Ellsworth
the ticalc.org project
davidell@ticalc.org
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