AT89C5115
PCA Modules
Each one of the two compare/capture modules has six possible functions. It can
perform:
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16-bit Capture, positive-edge triggered
16-bit Capture, negative-edge triggered
16-bit Capture, both positive and negative-edge triggered
16-bit Software Timer
16-bit High Speed Output
8-bit Pulse Width Modulator.
Each module in the PCA has a special function register associated with it (CCAPM0 for
module 0 ...). The CCAPM0:1 registers contain the bits that control the mode that each
module will operate in.
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The ECCF bit enables the CCF flag in the CCON register to generate an interrupt
when a match or compare occurs in the associated module.
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The PWM bit enables the pulse width modulation mode.
The TOG bit when set causes the CEX output associated with the module to toggle
when there is a match between the PCA counter and the module’s capture/compare
register.
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The match bit MAT when set will cause the CCFn bit in the CCON register to be set
when there is a match between the PCA counter and the module’s capture/compare
register.
The two bits CAPN and CAPP in CCAPMn register determine the edge that a
capture input will be active on. The CAPN bit enables the negative edge, and the
CAPP bit enables the positive edge. If both bits are set both edges will be enabled.
The bit ECOM in CCAPM register when set enables the comparator function.
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4128F–8051–05/06
ATMEL [ ATMEL ]
