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56F805EVM Hardware User’s Manual
MOTOROLA
2.4 Clock Source
The 56F805EVM uses an 8.00MHz crystal, Y1, connected to its External Crystal Inputs,
EXTAL and XTAL. The 56F805 uses its internal PLL to multiply the input frequency by
10 to achieve its 80MHz maximum operating frequency. An external oscillator source can
be connected to the hybrid controller by using the oscillator bypass connectors, JG6 and
JG18; see
.
Figure 2-3. Schematic Diagram of the Clock Interface
2.5 Operating Mode
The 56F805EVM provides a boot-up MODE selection jumper, JG7. This jumper is used
to select the operating mode of the device as it exits RESET. Refer to the
DSP56F801/803/805/807 User’s Manual for a complete description of the chip’s
operating modes.
shows the two operation modes available on the 56F805.
Table 2-2. Operating Mode Selection
Operating Mode
JG7
Comment
0
1–2
Bootstrap from internal memory (GND)
3
No Jumper
Bootstrap from external memory (+3.3V)
56F805
EXTERNAL
OSCILLATOR
HEADERS
JG6
3
2
1
1
2
EXTAL
XTAL
JG18
8.00MHz
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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