[comp.sys.amiga] Amiga Transformer

phils@tekigm2.UUCP (03/05/87)

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Having a (very) occasional need to use PC-DOS (for very short periods of
time), I bought a 5 1/4" drive for my Amiga, knowing full well about
warnings that Transformer didn't work on 1.2. 

I also have the CMI Kickstart Eliminator. Which presents the problem: How do
I use Transformer, if I can't boot Kickstart 1.1.

Well, I did a little hacking and managed to patch Transformer to work on
1.2. The question now is "is anybody else interested?" I could easily build
a very short program to automate the patch and post it to the net (there are
only 7 bytes to patch), but before I do, I'd like to know if anybody
else is in need of it.

At any rate, here is a list of differences. All the changes are in the file
"at1":

File offset		Old value	New value

0081			6A		B8
010F			0C		10
0121			24		20
0133			28		2C
0145			2C		30
0173			6A		B8
0179			6A		B8

Yeah, I know about the limitations, but for no more than I need it, it 
serves me just fine.
-- 
-------------------------------------------------------------------------------
Phil Staub              tektronix!tekigm!phils    (206) 253-5634
Tektronix, Inc., ISI Engineering
P.O.Box 3500, M/S C1-904, Vancouver, Washington  98668

phils@tekigm2.TEK.COM (Philip E Staub) (03/05/87)

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OOPS!

I forgot to mention that when using the patched Transformer with the CMI
Kickstart eliminator, the WCS ram must *not* be AddMem'ed into the system.
I don't know if Transformer running under 1.1 could deal with AddMem'ed
memory. I suspect it didn't. I also don't know what the patched Transformer
will do with auto-config memory expansion (I don't have any to try it with).
-- 
-------------------------------------------------------------------------------
Phil Staub              tektronix!tekigm!phils    (206) 253-5634
Tektronix, Inc., ISI Engineering
P.O.Box 3500, M/S C1-904, Vancouver, Washington  98668

phils@tekigm2.TEK.COM (Philip E Staub) (03/06/87)

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Since the patch program to patch the Amiga Transformer for 1.2 operation
turned out to be so short, I might as well post it. 

Some caveats:

1. Once you patch "at1" for 1.2 operation, it will no longer work under 1.1.
Of course, make sure you're not patching your original disk.

2. I haven't attempted to determine why it won't work with AddMem'ed memory.
I just make sure my startup-sequence doesn't have the AddMem I normally use
to make the CMI Kickstart Eliminator RAM accessible.

3. I haven't tried it with any kind of auto-configure memory.

4. Although this program works fine when compiled with both the Manx
compiler on my Amiga and the BSD 4.3/System V compiler on our Gould 9000, no
promises that it will work with Lattice. But there's no magic here, so it
should work on any flavor of compiler.

5. Although I have used the patched Transformer briefly, I haven't fully
wrung it out to see what bugs there might be. Since I hadn't used it under
1.1, I really don't know whether there may be other things which may need to be
patched to make it work at least as well as it did under 1.1. But for me,
for now, it boots MS-DOS and seems to work ok. Thats really all I'm
interested in (for now).

------------------------------ cut here -----------------------------------
/*	ATPatch.c - Patch the Amiga Transformer for operation under 1.2 */

#include "stdio.h"

main()
{
	FILE	*fp, *fopen();

	fp = fopen("at1","r+");
	fseek(fp,0x81L,0);
	putc(0xb8,fp);
	fseek(fp,0x10fL,0);
	putc(0x10,fp);
	fseek(fp,0x121L,0);
	putc(0x20,fp);
	fseek(fp,0x133L,0);
	putc(0x2c,fp);
	fseek(fp,0x145L,0);
	putc(0x30,fp);
	fseek(fp,0x173L,0);
	putc(0xb8,fp);
	fseek(fp,0x179L,0);
	putc(0xb8,fp);
	fclose(fp);
}
-- 
-------------------------------------------------------------------------------
Phil Staub              tektronix!tekigm!phils    (206) 253-5634
Tektronix, Inc., ISI Engineering
P.O.Box 3500, M/S C1-904, Vancouver, Washington  98668