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Re: Why did Woz use the long cycle?
> VA already toggles every line. It counts just as /HPE is asserted, and
> then holds it's own value as the horizontal counter is preset. VA isn't
> preset when vertical preload occurs, but since there is an even number of
> vertical cycles, it doesn't need to be preset at that point, either.
>
> Jim Salter's schematic in his book is mistaken when it connects /HPE to VA
> and the VA preset line. /HPE is not connected to either.
Are you sure that it is Understanding Apple II+ book? Which page did
Jim Sather make mistake to connect HPE to VA.
Bryan Parkoff