Re: How do I add firmware to a card?

[heuser.marcus@freenet.de]

RedskullDC schrieb:
> "David Empson" <dempson@actrix.gen.nz> wrote in message
> 1hsc1jh.1hqbl6aapwbr5N%dempson@actrix.gen.nz">news:1hsc1jh.1hqbl6aapwbr5N%dempson@actrix.gen.nz...
>
> > I don't recall whether the 65C02 in the UniDisk 3.5 runs at a higher
> > clock speed than the Apple II: if data is transferred between the
> > UniDisk CPU and the 3.5" drive mechanism under processor control then it
> > would need to run at about 2 MHz (or faster) to be able to keep up with
> > the data rate (16 microseconds per byte, which is twice as fast as a
> > 5.25" drive). If they used some form of DMA, then the UniDisk's CPU
> > could be running at the same clock speed as the Apple II.
>
> The IIgs firmware manual covers the smartport calls , and the internal
> memory map for the 65C02 in the Unidisk3.5.
>
> It uses an IWM chip which is clocked at 7MHz to achieve the 16ms/byte
> you mention. The 65C02 is running at 2MHz.

How much RAM does the drive have?

bye
Marcus