[Coco] PBJ P-C Pack

[Gene Heskett]

Greetings;

I just looked at the manual Bruce was good enough to fwd to me, and two things are noteworthy.

1.  It contains no copyright notice.  Whoopee!

2.  It is addressed at $FF90-93.  Ok for a coco or coco2, deadly for a coco3 as that is the I/O port controlling the 
gime's memory mapping.

So the first thing that will be needed is to re-wire the decoding to put it at a more usable for the coco3 address of 
someplace below $FF7C, probably $FF78.  The MPI uses $FF7F for its mode latch, so that $FF7C is pretty well off limits.

I just reloaded it, and turned it in acroread so the coco is to 
the left, but it will take a bit to decode what PBJ did with the 
decoding, but I suspect that if U7, pins 11 (input) and 10 (output)
were cut loose and the trace jumpered from A3 straight to U8 pin 10, 
then A3 will have to be high which will be $FF98, but then use the 
cut loose section of U7 to invert A5 on its way to U8 pin 7 which 
should convert it to $FF78.  Unless I'm getting oldtimers that is.. :)

If you already have something at that address Daniel, then cut and 
patch accordingly to put it someplace that is compatible.  And of 
course adjust the driver srcs before you build it.

I would to verify, redraw that schematic such that the address lines 
are all in order so that the power of 2 scheme stands out a lot 
clearer, and then you can play what if to get the logic right.

For an $FF78 base address, (and I'm about to crash, I just had a 
30 second lockup) you would want this binary pattern:

 1111111101111000 with address line A15 on the left & A0 on the right.

The about to crash remark is apparently I have a perfectly good 
disk according to its own self test, about to die.  The logs 
are being spammed with this:
---------------
Jan 27 21:58:55 coyote kernel: [ 2121.027713] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
Jan 27 21:58:55 coyote kernel: [ 2121.027725] ata1.00: cmd 35/00:a8:d9:ce:09/00:01:00:00:00/e0 tag 0 dma 217088 out
Jan 27 21:58:55 coyote kernel: [ 2121.027727]          res 40/00:01:00:4f:c2/00:00:00:00:00/00 Emask 0x4 (timeout)
Jan 27 21:58:55 coyote kernel: [ 2121.027730] ata1.00: status: { DRDY }
Jan 27 21:58:55 coyote kernel: [ 2121.027758] ata1: soft resetting link
Jan 27 21:58:55 coyote kernel: [ 2121.190003] ata1.00: configured for UDMA/100
Jan 27 21:58:55 coyote kernel: [ 2121.190020] ata1: EH complete
Jan 27 21:58:55 coyote kernel: [ 2121.212540] sd 0:0:0:0: [sda] 390721968 512-byte hardware sectors (200050 MB)
Jan 27 21:58:55 coyote kernel: [ 2121.212910] sd 0:0:0:0: [sda] Write Protect is off
Jan 27 21:58:55 coyote kernel: [ 2121.213173] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't 
support DPO or FUA
----------------

Sigh, it only has 27605 POH on it too.  2nd newest drive in the box!

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Q:	How many Harvard MBA's does it take to screw in a light bulb?
A:	Just one.  He grasps it firmly and the universe revolves around him.