PC-bioxx/Openxbox bank switch
(v0.1)
Tutorial
written
by : Arakon
Last edited:
August 30, 2003
This
modification
will allow
users
of the
older
style
PC-Bioxx
to switch
between
2 512
kb banks.
I did
this because
I am using
the xbox
with the
bioxx
mostly
for Linux
experimenting,
but wanted
to play
halo on
it occassionally
too. now
I can
switch
between
cromwell
and an
x2 bios.
This
mod is
NOT for
beginners..
it requires
precision
and good
tools.
If you
fuck your
chip up,
that's
your problem,
not mine.
"up/top"
is where
the parallel
port connector
is.
Locate
the A18
pin of
the flashrom
(bottom
left in
the pic,
the leftmost
trace
before
the gap
in traces).
CAREFULLY
scratch
off the
green
coating
(I used
a needle),
about
1-2 mm
long,
before
the trace
runs towards
the side.
you can
basically
scratch
anywhere,
I just
found
this to
be a good
place.
clean
the dust
of the
coating
off, then
apply
a little
solder
to the
copper
so you
can solder
to it.
now cut
the trace
behind
the part
you scratched,
(NOT between
scratched
part and
flashrom
pin!).
Solder
a wire
to the
area you
scratched.
solder
a wire
each to
the top
of the
2 capacitors
as shown
in the
first
pics.
Now solder
the wire
from the
trace
to the
middle
pin of
a SPDT
switch
(2 positions,
3 pins),
and the
wires
from the
capacitors
to the
other
2 pins.
tape
or glue
down the
wires
carefully
after
testing.
click
image
for full
view
Flashing
instructions:
the bioxx
flasher
software
won't
recognize
the switchability,
so you
have to
manually
flash
the 2
parts.
erase
will work
regardless
of position.
now make/take
a 1 MB
version
of the
2 bioses
you want
to use.
erase
the bioxx,
then load
the first
bios and
flash.
it should
give an
error
at around
0x08000
(if it
doesn't,
don't
worry).
now flip
the switch,
load the
second
bios,
and flash
(without
erasing
again).
after
that,
turn off
the box
and try
both switch
positions.
it SHOULD
give you
a different
bios in
each position.
if not,
erase
and try
flashing
in the
opposite
switch
position
order
(i.e.
if you
tried
switch
up, then
down and
it fails,
try down,
then up).
Tutorial
written
by : Arakon
