ssm2163p Analog Devices, Inc., ssm2163p Datasheet - Page 16

• Manufacturer Part Number: ssm2163p
• Description: Digitally Controlled 8 X 2 Audio Mixer
• Manufacturer: Analog Devices, Inc.

SSM2163
number stored in LEVEL_VALUE is the attenuation value,
expressed in –dB, so larger values will decrease volume. Also,
the register must not be allowed to increment beyond 7FH
because the MSB will be set and the SSM2163 will interpret
the value as an address. Therefore, the two highest bits of
LEVEL_VALUE should be cleared by ANDing the register
with 3FH.)
If the C’s hardware serial port is being user for other purposes,
the SSM2163 can be loaded by using the parallel port. A typical
parallel interface is shown in Figure 31. The serial data is
transmitted to the SSM2163 via the 80C51’s Port 1.6 output,
while Port 1.5 acts as the serial clock.
Software for the interface of Figure 31 is straightforward.
Typically, the C will repeatedly shift the value to be sent, for
example from register LEVEL_VALUE, into the carry bit. Port
P1.6 is then set or reset based on the carry bit, and Port P1.5 is
strobed low and then high to create a clock pulse. After eight
loops, the value will have been sent to the SSM2163. Note that
all eight bits should be sent, even though only six bits are
significant. If only six bits are shifted in, the two low order bits
of the previous value will remain in the MSBs of the shift
register. If this action results in the MSB being a one, the
SSM2163 will interpret this as an address and unpredictable
results will occur.
Figure 31. An SSM2163 to 80C51 C Interface Using
Parallel Port 1
80C51 µC
NOTE: ADDITIONAL PINS OMITTED FOR CLARITY
P1.6
P1.5
P1.4
P1.3
+5V
10k
DATA IN
CLK
WRITE
LD
SYSMUTE
SSM2163
–16–
0.0118 (0.30)
0.0040 (0.10)
0.250
(6.35)
MAX
0.200 (5.05)
0.125 (3.18)
29
1
PIN 1
28
1
PIN 1
0.022 (0.558)
0.014 (0.356)
0.0500
(1.27)
BSC
Dimensions shown in inches and (mm).
1.565 (39.70)
1.380 (35.10)
0.7125 (18.10)
0.6969 (17.70)
OUTLINE DIMENSIONS
0.0192 (0.49)
0.0138 (0.35)
28-Pin Plastic DIP
0.100
(2.54)
BSC
28-Pin SOIC
(N-28)
(R-28)
0.070
(1.77)
SEATING
MAX
PLANE
0.060 (1.52)
0.015 (0.38)
15
14
0.1043 (2.65)
0.0926 (2.35)
14
15
0.580 (14.73)
0.485 (12.32)
SEATING
PLANE
0.0125 (0.32)
0.0091 (0.23)
0.150
(3.81)
MIN
0.625 (15.87)
0.600 (15.24)
8
0
0.0291 (0.74)
0.0098 (0.25)
0.0500 (1.27)
0.0157 (0.40)
0.015 (0.381)
0.008 (0.204)
0.195 (4.95)
0.125 (3.18)
REV. 0
x 45