oyster@uwmacc.UUCP (Vicious Oyster) (11/21/85)
Regarding queries about and problems with the BYTE DOS for 256K, here's
what's in the MAAUG October newsletter:
[Start newsletter excerpt]
...the new Atari 130XE comes with DOS 2.5 which already supports a RAM-disk
as D8:. DOS 2.5 will work with our memory upgrade without modification;
however, since the 130XE only comes with 128K, DOS 2.5 has no way of knowing
about the extra memory that our modification provides.
The following is a description of how to modify DOS 2.5 in order to provide D8:
with a full 720 sectors (instead of the 512 sectors provided); and to add D7:
with 720 sectors. This procedure is included for the benefit of other users
groups... MAAUG members need not read this section since they can get the
patched DOS at the MAUUG meeting. You will need an ASSEMBLER cartridge to
install this patch:
1) Insert your assembler cartridge.
Put DOS 2.5 in drive 1.
Cold start your machine.
2) When the "EDIT" prompt appears, get into debug mode by typing: "BUG".
3) When the "DEBUG" prompt appears, get into the mini-assembler by typing "A".
4) Type the following lines ending each by pressing the RETURN key. The mini-
assembler will respond to each line with one or more lines of assembled object
code. Notice that you MUST type a space after each '<' sign (which denotes the
end of the address and the start of the instruction).
B86< LDX #0
105C< LDA #$64
12DE< LDY $21
< CPY #8
< BCC *+4
< ADC #5
< TAY
< LDA $185B,Y
< JMP $1846
148D< CMP #6
14C4< LDA #$70
< JSR $1846
183A< .BYTE "MEM.SAV ERR",$9B
1846< STA $44
< LDA $D301
< AND #$83
< ORA $44
< STA $D301
< RTS
185B< .BYTE $20,$24,$28,$2C
< .BYTE $40,$44,$48,$4C
< .BYTE $60,$64,$68,$6C
77F< CPX #7
< BCC $78A
B88< CMP #7
< BCS $BD3
105E< CPY #7
< BCS $1076
70A< .BYTE $C3
5) Press the RETURN key to exit the mini-assembler mode.
6) Type "X" followed by RETURN to return to the EDIT mode.
7) Type "DOS" to access the DOS menu.
8) Write the DOS files out to drive 1.
9) Turn off the machine and cold start DOS... when you do a directory of
D8: you should now have 620 sectors free (instead of 499). Use the "I"
command to format D7:. When you do a directory of D7: you should have
707 sectors free. (D8: is automatically formatted by the "RAMDISK.COM"
program if present on the disk when DOS is loaded.)
10) Pat yourself on the back... you now have two full-sized RAM-disks.
Note: this patch will only drive 256K. A single patch to drive either the
256K or 512K will be forthcoming as soon as we have a working 512K memory
upgrade installed.
==========
QUIRKS
==========
Don't erase DOS.DUP or MEM.SAV from D8:
Don't write DOS files to D5: thru D7:
Don't try to copy MEM.SAV
Don't count on the Duplicate disk function always working between RAM-disks
Don't turn off your machine and expect data written only to a RAM-disk to
still be there when you turn it back on.
Don't run any 130XE programs that use extra memory without first saving any
data that you need to keep from your RAM-disks to a real disk. (For example
a sector copier.)
Don't expect all the 130XE software to work since there is one function of
that machine which is not duplicated by this memory upgrade...namely, the
extra memory video chip enable line (PB5) is being used by us as an address
line.
Two DOS error messages were shortened/disfigured in order to make room for
these patches. They are "Type Y to still run DOS" and "ERROR-saving user
memory on disk". The latter now reads: "MEM.SAV ERR" and the former now
is illegible (Asi es la vida).
If the 512K version of the upgrade is installed, then the self-test feature
of the 800XL must be sacrificed.
Disclaimer: The information contained in the articles in the MAUUG Newsletter
are intended for general distribution as the property of the Madison Area ATARI
User's Group. The information is free and may be used in any way which is
generally assumed to be appropriate by any individual or group of individuals
as long as no financial compensation is incurred. Neither the articles nor the
information contained in them is to be sold or distributed in exchange for
money.
ATARI is a copyrighted name and all of its products are protected by
copyright.
[End newsletter excerpt]
Further caveats:
Don't change your original copy of DOS!! Change a copy.
There's a small chance that I confused a "B" with an "8" in the above
instructions, due to the fact that the newsletter is done using a dot-matrix
printer with less than perfect resolution.
Further news:
The MAAUG now has a couple of 512K 800XL's.
They are still having a few problems with the 1200XL upgrade, but they just
started working on it last week, so I'm keeping my fingers crossed.
I'm still trying to keep names of anybody who wants further info.
Personal disclaimer: I'm neither a hardware hacker, an OS wizard, nor an
official representative of the MAAUG. Also, my employer has no connection
with the MAAUG, and doesn't know what I do during my coffee breaks.
- Joel Plutchak
{allegra,ihnp4,seismo}!uwvax!uwmacc!oyster