Motorola DSP56824ADM, User Manual

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2-8 DSP56824ADM User’s Manual MOTOROLA
DSP56824ADM Technical Summary
Jumper Configuration
2.6.1 Clock Input Selection
The clock input to the DSP is selected by jumper group JG1. There are two options for
the clock input selection. The DSP clock source can be the on-board user clock oscillator.
Alternatively, an external clock input can be connected via the J2 expansion connector or
applied directly to JG1 Pin 3. See Table 2-1.
Note: The DSP56824ADM is factory configured to use the on-board 10 MHz clock
oscillator (U12).
2.6.2 User Clock Oscillator V
CC
Setting
Jumper group JG9 is used to select the power source (3.3 V or 5.0 V) for the Clock
Oscillator (U12). Jumpering pins 1–2 on JG9 s3.3 V. Jumpering pins 2–3 on JG9
selects 5.0 V, the default setting. The output signal at the clock oscillator is buffered and
inverted before being sent to the DSP. See Table 2-2 for details.
Note: The DSP56824ADM is factory configured for clock V
CC
to be +5 V.
2.6.3 Operating Mode Selection
Jumper group JG2 selects the operating mode of the DSP after reset. Refer to the
DSP56824 User’s Manual for a complete description of the chip’s operating modes.
Programs can be loaded from NVSRAM by configuring the DSP to exit reset in
Table 2-1 Clock Source Selection
Clock Source JG1
10 MHz user oscillator clock (default) 1–2
External clock CLOCK_IN on J2 pin 1 3–4
Table 2-2 Oscillator V
CC
Selection
JG9 Comment
1–2 Clock V
CC
is +3.3 V
2–3 Clock V
CC
is +5.0 V (default)