Reflex Service Manual
Performance Verification
Audio
I/O Test
(8)
This
test
loads
a
microcode
program into
the
Lexichip
(U14)
which
passes
converted
audio
directly
to
the DAC
(U24) for
output
with processing.
The
code
is loaded, the
+
sign
is flashed,
and
you
are returned
to
the
diagnostics
menu with
the
I/O program running. The
I/O remains running until
another
diagnostic changes the
Lexichip
WCS.
Please note
that
this
version of the I/
O program
has
alternate memory
access to offset
0
and
FFFF,
to
induce
digital noise like
that of
a
typical reverb program.
Return
to
normal
operating
mode
(9)
This
allows
you to
exit the
diagnostics and return
to
the
regular operating
system. Changes
to the
MIDI
configuration are
kept
intact
and
the size of the
DRAM
is calculated. Note
that the
MIDI
configuration
will
be
erased
if
the
SRAM
test
is
run. The MIDI channel will
end
up
being
channel 1
because
the
SRAM
test
clears
the
RAM
to 0
when
it
is done.
EEPROM checksum
(10)
This
test
reads each
b^e in
the User Register portion of
the
EEPROM
(U7)
and
adds
them
to
calculate
a
checksum. This
value is compared
with
the
checksum
value
stored
in
the
EEPROM
itself.
This
checksum
is recalculated
each time
a
register
is stored.
MIDI
Wrap Around
Test
(11)
This
test
checks
the
operation of the UART
(U2)
and
MIDI IN
and
OUT
hardware
by
transmitting
a
series of characters
to
the
MIDI
OUT
port and
reading the MIDI IN
port
to
see
if
the
data matches.
Before
transmitting data
the UART is checked for
data waiting
to be
transmitted. If this part of the
test
fails
the
UART itself
may
be bad, the 500KCLK
clock may
be
missing
or the
address line (SADRO)
to
the
chip
may
be
open.
Data is then
read from
the
UART
and the
UART
is asked
if
it has
data
waiting (which
it shouldn’t because
it
was
just
read). Note that
the C/D
pin
on
the
UART
controls
whether
we
are
communicating
data(O) (transmit
or receive)
with
the
UART
or control/status
(1
).
If
it
is stuck
low, then
data can
only
be
sent and received
with
no
control
or
status.
Stuck
high
means that
we
can
only
read
status
and send
control
information
to
the
chip. For
this
test to
pass
this bit
must toggle.
At this point,
data
is sent
to
the
UART.
After
an
interval
long
enough
for
the
UART
to
transmit the
byte, the
status register
in
the UART
is
read
to see
if
the
byte
was transmitted.
The
status
register
is
then read again
to see
if
a byte
has
been
received.
If
so,
the
byte
is read
from
the UART
and
checked against
the
byte
transmitted
to see
if
they
match.
This
repeats
until
the
entire
string
has
been
tested.
The
bytes
tested
are the ASCII
equivalents forthe
following
string:
“Does this
thing
actually
work??”,
followed
by
the
hex
values
AA
(1
01
0
1010 binary)
and
55
(0101
0101
binary).
While
the
test
is
running
the letter
r
is displayed.
The following error codes are
reported
for
this
test:
1
the buffer
initially
was not
empty
2
the receive buffer should
be empty
but
is
not
3
the
transmit
buffer should
be
empty
but
is
not
4 the
receive buffer should have
data but
doesn’t
5
data sent
doesn’t match the
data
received
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