Re: A86: 86 interrupts?
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Re: A86: 86 interrupts?
> Do any of you guys know if the link port is messed with in any
> of the interrupts? I've noticed that when you plug in a link
> cable (I.E a PC || link) the cursor will freeze for a second or
> so. Seeing as how the link port probably does not generate
> a physical insertion interrupt (there is no switch in it, I don't
> think) I'm wondering how the calculator knows a link cable has
> been inserted. What I think is happening is the ground band of the
> cable is coming in contact with the signal lines as the connector
> is inserted and the calculator times out waiting for another 7
> bits and/or an acknowledge for the one erroneous bit. However,
> in order for it to detect this bit at all there has to be something
> actively examining the TI link port when the calculator is at the
> home screen.
>
> If there is indeed a link port interupt, would it need to be disabled
> for a user assembly program that is using the link port? The E2-86
> driver is causing all sorts of random timeouts and I'm wondering if
> there isn't some interrupt I don't know about playing with the link
> port along with my driver.
All calculators with CBL support (everything except very old TI-85's)
have a linkport interrupt. This is used for silent linking and the trans-
fer of variables from a TI-Basic program. The calculator freezes for
a second when you insert a non-tapered link into the linkport because
it briefly touches two of the contacts at once. This sends some bit
to the link that makes the calculator wait for data. After a few
seconds, it times out.
In order to use the linkport, you have to use the ROM linkport
routines. Failure to do so would result in random errors triggered
by the interrupt. You would need to disable the interrupts to
prevent this.
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