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Chip Configuration
Mode
Master mode
Single-chip mode
Reserved
Reserved
1
Modifying the default configurations is possible only if the external RCON pin is asserted low.
During reset, certain module configurations depend on whether emulation mode is active
as determined by the state of the internal emulation signal.
30.6.3 Boot Device Selection
During reset configuration, the CS0 chip select pin is optionally configured to select an
external boot device. In this case, the V (valid) bit in the CSMR0 register is ignored, and
CS0 is enabled after reset. CS0 is asserted for the initial boot fetch accessed from address
0x0000_0000 for the Stack Pointer and address 0x0000_0004 for the program counter
(PC). It is assumed that the reset vector loaded from address 0x0000_0004 causes the CPU
to start executing from external memory space decoded by CS0.
30.6.4 Output Pad Strength Configuration
Output pad strength is determined during reset configuration as shown in Table 30-12.
Once reset is exited, the output pad strength configuration can be changed by programming
the LOAD bit of the chip configuration register.
Table 30-12. Output Pad Driver Strength Selection
Optional Pin Function Selection
Output pads configured for partial strength
Output pads configured for full strength
1
Modifying the default configurations is possible only if the external RCON pin is asserted low.
30.6.5 Clock Mode Selection
The clock mode is selected during reset and reflected in the PLLMODE, PLLSEL, and
PLLREF bits of SYNSR. Once reset is exited, the clock mode cannot be changed.
Table 30-13 summarizes clock mode selection during reset configuration.
MOTOROLA
Table 30-11. Chip Configuration Mode Selection
MODE2
D26 driven high
D26 driven high
D26 driven high
D26 driven low
Chapter 30. Chip Configuration Module (CCM)
CCR Register MODE Field
MODE1
D17 driven high
D17 driven high
D17 driven low
D17 don't care
CCR Register LOAD Bit
D21 driven low
D21 driven high
Functional Description
1
MODE0
D16 driven high
D16 driven low
D16 driven high
D16 don't care
1
30-11
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