Sage II - Page 91

SAGE
rr
sERvrcE
MANUAL
[1.0J
HARDWARE
CHANGES
ON
SAGE
II
CHANGES
FROM
CBOOO2
TO
CBOOO2B
XIX.O5
CHANGES
FROI,i
C80002
TO
CB0002B
:
The
flrst
150
C80002
boards
needed
U55
(7405)
pin
7
wlred
ro
ground.
A11 were
modified
in
the
factory.
Reslstors
R7
&
R6 were
located
too
close to a
trace
on the
back
of
the
board.
Solder
brldges
were
conmon
so resistor
pads
were
moved.
Mounting
holes
were
sllghtly
changed
to work
better wtth
the
Wlnchester
board
C80003,
The floppy
connectors
were
moved towards
the
rear
of the
board
about
I/ 4
to
l/2
inch
as
the
bay was
too
close to
the
mountlng
holes.
A
few
systems
were
shtpped
in
December which
nay have
had
underrated
caPacitors
(
0A
uf
6V)
across
the
l2v supplies.
These
IIUST
be replaced
with
lOuf
25V capacitors
REGARDLESS
of
whether
they
seem
to
cause
problens
or not.
The straps
as
shown
ln
older
Users'Manuals
(before
verslon
[1.4J
)
and
thelr
schematlcs
do not
match
thls
board.
I'he
maln dlfference
ls
ln how
the
straps
are named.
However
STRAP
506
for
the
CTS slgnal
IS wrong.
C80002
was
connected
as
shown
below.
If the user
attemptg
to strap
CTS
htgh
tAl
(+5v)
a short
w111
exisr
to *12r,'-
To
drive
CTS'
cut
the
trace
from
pln
6
to
ptn
5.
Cut
the
trace
from
tBl
to
pln
6. Rewlre
pln
5
to
[BJ.
Also
cut
+I2V
from
pln
6
and
connect
pln
6
to
U59-1.
u61-4
I
o
Jl0-pln
ll5. CTS
+svtAl
tl---tBl----,
I
--o
J
10-pln
116 DSR
I
+12V
CBOO2A
was
connected
so
that
crs is normally
held
hlgh.
To
drlve
CTS, the
strap
from
tA]
must be
cut.
u6 1-4
I
+l2v
tAl------t
l---tBl-------o
JtO-pln
lts
crs
U59-l
-----------o
Jl9-pin
lt| DSR
Strap
S07 was
labeled
on
the
silkscreen:
TX2
I
rxEUss-18
tAl
il-----tBlu58-l5rxRDy
82