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Re: "SmartWatch" for No-Slot-Clock?
In article dempson@actrix.gen.nz (David Empson) writes...
>
>In article <31JUL199622595506@vax2.concordia.ca>, spec@vax2.concordia.ca
>(Mitchell Spector) wrote:
>
>> I now have both of the above programs, however something odd is up.
>>Both programs claim they _cannot_ detect a No-Slot-Clock when the chip
>>is installed in my Apple IIc Plus. Plugging it into one of my Apple IIc's
>>(a ROM 255) detects it and lets me set the time/date. I've transplanted
>>the NCS back into the IIc Plus, and it's retained the correct time and
>>date thankfully, but why is this happening?
>
>Have you disabled the accelerator? The No Slot Clock operates by
>appearing to modify the state of one bit of a ROM location (it provides a
>64-bit serial data stream through this one bit). The ZIP (or equivalent,
>such as the IIc+) caches the ROM location, so the software never sees the
>changing bit.
No, but I have now and of course _now_ it works. I feel so silly having
overlooked such an obvious source of the problem, rather like someone who
finds out the machine is unplugged after going through a dozen other steps! :)
>To access a No Slot Clock requires turning off the ZIP first. The driver
>may be doing this, but the time setting programs may not.
I wasn't aware of this, although disabling the "Zip" didn't cross my
mind since I'm so used to all my 8-bit Apple II's running at 1 MHz. It
keeps slipping my mind that the IIc Plus has built-in acceleration. :)
Mitchell Spector
spec@vax2.concordia.ca