Sony CXD2701Q Data Book page 118

SONY,
CX01160AP/AQ
ACC
Register
(5)
MPY
MOA
Selector
MOB
Selector
MPY
(6)
AU
AOA
Selector
AOB
Selector
AU
Clipper
Barrel Shifter
This 34bit long register
stores
AU
operation
results.
However
curing
comparison
commands
{'ACC-R'
or
'ACC-4R') values
are not renewed.
Selects
either
K-RAM
data or
data from various registers called out through
the
bus, by
means
of the multiplying
command.
Selects either
DRAM
data or
data from various
registers called
out through the
bus, by
means
of
the multiplying
command.
Data
selected by
means
ol
the
above
2 selectors
is
multiplied together.
There
are
4
ways
of
multiplying
K*D, K*X,
X*D
and X*X.
Also 4
multiplying
modes
16b*16b, 16b*32b,
32b*i6b and
32b#32b.
Selects either
ACC
or
O
by
means
of
AU command
Selects either
P
(33b) or
H
(32b)
to
convert
into
34
bit
length
Data
selected by
means
of the
above
2 selectors
is
either
added, subtracted,
turned
into
absolute value
or
compared
together.
When
ACC
data
is
transferred
or multiplied,
or sent
to
the
below mentioned
barrel shifter via
the bus,
clip
processing
is
executed
on
the 34bit length
to
obtain
a
32bit length.
During transfer or multiplying the
upper
16bit of
this
output
(ACCH) and
the lower
16bit
(ACCL) can be handled independently
ACC
value
passed
through
the clipper
can be handled as
follows
1)
converted
into
positive
value
floating point
form
2)
arithmetic
left
shift
executed
3)
arithmatic
right shift
executed.
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