Re: Trouble with Apple //e & Unidisk 3.5 & 4mhz. ZIP chip

[supertimer@aol.com (Supertimer)]

ehillman@erinet.com (Ed Hillman) wrote:

>As an update to my first post:
>
>I received a response via e-mail that another person has had no
>trouble with a zipchip/unidisk combination.  He suggested I try
>setting the zip chip with slot 5 (unidisk) set fast. This did not
>help. 
>
>Since I have recently upgraded to newer ProDOS and a different clock
>driver, I tried ging back to the older version of ProDOS (1.8). Still
>no luck.
>
>I have for the time being removed the zipchip and replaced the 65C02.
>Since I'm not running any real speed demanding programs, this is my
>best current option.
>
>Any ideas out there?

Try pulling the CP/M card.  ZipChip is not DMA compatible,
so the CP/M card might be messing something up when
used with the ZipChip such that the UniDisk can't work.