docs: README.buddha: convert to ReST and add to m68k book

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Amiga Buddha and Catweasel IDE Driver

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The Amiga Buddha and Catweasel IDE Driver (part of ide.c) was written by

Geert Uytterhoeven based on the following specifications:

example leaving some address lines out of the equations...).

If you want to configure the board yourself (for example let

a  Linux  kernel  configure the card), look at the Commodore

Docs.  Reading the nibbles should give this information:

Docs.  Reading the nibbles should give this information::

  Vendor number: 4626 ($1212)

  product number: 0 (42 for Catweasel Z-II)

The local memory-map is even active when mapped to $e8:

==============  ===========================================

$0-$7e		Autokonfig-space, see Z-II docs.

$80-$7fd	reserved

		chip. The addresses $0 to $fff of the rom

		chip cannot be read. Rom is Byte-wide and

		mapped to even addresses.

==============  ===========================================

The  IDE ports issue an INT2.  You can read the level of the

IRQ-lines  of  the  IDE-ports by reading from the three (two

versions  (if  I'll  ever  update this one).  I presume that

I'll  never use the lower four bits, but they have to be set

to 1 by definition.

The  values in this table have to be shifted 5 bits to the

left and or'd with $1f (this sets the lower 5 bits).

(exactly 70,5 at 14,18 Mhz on PAL systems).

value 0 (Default after reset)

  497ns Select (7 clock cycles) , IOR/IOW after 172ns (2 clock cycles)

  (same timing as the Amiga 1200 does on it's IDE port without

  accelerator card)

value 1

  639ns Select (9 clock cycles), IOR/IOW after 243ns (3 clock cycles)

value 2

  781ns Select (11 clock cycles), IOR/IOW after 314ns (4 clock cycles)

value 3

  355ns Select (5 clock cycles), IOR/IOW after 101ns (1 clock cycle)

value 4

  355ns Select (5 clock cycles), IOR/IOW after 172ns (2 clock cycles)

value 5

  355ns Select (5 clock cycles), IOR/IOW after 243ns (3 clock cycles)

value 6

  1065ns Select (15 clock cycles), IOR/IOW after 314ns (4 clock cycles)

value 7

  355ns Select, (5 clock cycles), IOR/IOW after 101ns (1 clock cycle)

When accessing IDE registers with A6=1 (for example $84x),

Buddha.

Jens Schönfeld february 19th, 1997

updated may 27th, 1997

			     eMail: sysop@nostlgic.tng.oche.de

eMail: sysop@nostlgic.tng.oche.de

   :maxdepth: 2

   kernel-options

   buddha-driver

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