Motorola DSP56824ADM, User Manual

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2-6 DSP56824ADM User’s Manual MOTOROLA
DSP56824ADM Technical Summary
Voice Codec
2.3.2 Non-Volatile Static RAM (NVSRAM)
The DSP56824ADM provides two 32K
×
8-bit NVSRAM memory devices, installed as U9
and U10, to give a total of 32K
×
16-bit NVSRAM memory. External Program RAM must
be configured for operation in the lower program memory address space ($0000–$7FFF).
The NVSRAM memory automatically decodes to the upper program memory space
($8000–$FFFF) when enabled by JG13. Refer to section 2.6.4 Program Memory
Configuration
on page 2-9 for instructions on how to load a program into the SIMTEK
non-volatile portion of the NVSRAM.
2.4 VOICE CODEC
The DSP56824ADM analog section uses Motorola’s MC145483 13-bit linear codec,
installed at U17. Refer to the data sheet included with this kit for more information on
the MC145483. The DSP56824ADM has 1/8-inch stereo jacks for codec input and output.
Codec output jumper JG11 can select one of two separate output load drives. Refer to
Table 2-9
on page 2-14 for a description of the output load options. The codec interfaces
to the DSP via the Synchronous Serial Interface (SSI) provided on Port C of the
DSP56824. No glue logic is required. The codec clock and frame synchronization are
provided by the SSI. Jumper JG5 allows the user to disconnect the on-board codec
completely. See Table 2-6 on page 2-13. This frees the SSI port on the DSP56824 for other
peripheral use.
2.5 OTHER DSP56824ADM FEATURES
The DSP56824ADM provides these additional user features:
• User-replaceable clock oscillator
• Two on-board LED indicators
• Two on-board pushbutton switches
• Four on-board test points
These features are described in the following subsections.