Cpu Program; Test Mode - Roland SH-101 Service Manual

L
NOV.
1st,
1982
CPU PROGRAM
I
L
^
^
The
CPU
80C49-6-7301
controls the various
modes
and
functions
of
the
SH-101
through
a
series of
programmed
steps, as
shown
in
the attached flowchart. These actions
are described below.
C
POWER ON
)
Are
LOAD
and
KEY TRANSPOSE
buttons pressed?
NO
YES
1
YES
::
INITIAL
SET
RANGE DATA READ
I
RANGE DATA OUTPUT
I
KEYBOARD READ
I
CLOCK CHECK
I
RANDOM DATA
OUTPUT
8
I
FUNCTION SW READ
YES
12 CV
OUTPUT
13
I
GATE & LED DATA
OUTPUT
J
TEST
MODE
t
9
LOAD
—*
YES
*
10
PLAY
-
YES
t
11
ARPEGGIO
L
1
Note:
Steps
3
through
1
3 are
a series
of
program
steps
that
are sequentially
executed
by
the
CPU
at 1.5 to
3.5msec
intervals.
The
CPU
can modify
this se-
quence any
time
new
data
is
input.
1.
TEST
MODE
The
Test
mode
allows easy adjustment
of the
SH-101.
To
enter the Test
mode,
first
turn the
power
switch
Off.
This
is
necessary as the Test
mode
cannot
be
entered
while the
SH-101
is in
any of the normal operating
modes.
Now
simultaneously
press
both
the
LOAD
and
KEY TRANSPOSE
buttons and
turn the
power
switch
On.
The
CPU
sets the voltage
at
the
KCV
and
at
the
Range
to zero
and
turns the
Gate
Off.
The
unit
is
now
in
the Test
Mode. The
voltage values
at
the
KCV
and
the
Range, and
the status
of
the
Gate change
in
each
of
the function
modes
listed
below.
Function Button
KCV
Range Gate
PLAY
ARPEGGIO
DOWN
ARPEGGIO
U&D
ARPEGGIO
UP
LOAD
2.75V
2.5V
4.75V
OV
OV
OV
OV
4.75V
OV OV
Off
Off
On
On
Off
To
enter
a
normal mode,
either press the Hold button
down,
or
turn the
power
switch Off and
then
back
On
again.
2.
INITIAL
SET
The
CPU
performs
Initial
Set
when
the
power
switch
is
turned
On
or
when
the
HOLD
button
is
pressed during
the Test
mode.
This operation deletes
all
the data
that
is
stored
in
the
built-in
RAM,
such
as
Keyboard and
switch
mode
data, but does not delete the
Sequencer
data.
3.
RANGE DATA READ
The
CPU
reads
and memorizesthe
positions
of
the
VCO
Range,
TRANSPOSE
(L,
M
and
H)
and
GATE/TRIG
(LFO
)
switches.
4.
RANGE DATA OUTPUT
The
CPU
sends the
VCO
Range
data
(read
in
Step
3)
to
the
D/A
Converter
where
it is
converted
into
analog-
equivalent values.
RangeSelector Range Data
16'
8'
4'
2'
1V
2V
3V
4V
If
the
CPU
contains Key Transpose
data
(stored
during
step
8 of the previous
program
execution), the
Key
Shift
data
is
added
to the
Range
Selector data.
For example,
if
the user selects the
lowest F-key and
sets the
Range
Selector
to
16', the
Range
data value
will
be
0.417V.
Likewise,
if
the
user selects a higher
C-key and
sets the
Range
Selector to 2', the
Range
data value
will
be 5V.