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Reaction Module (REACM)
MPC5644A Microcontroller Reference Manual, Rev. 6
722
Freescale Semiconductor
Figure 23-22. Hold-off timer bank block diagram
The Modulation Control Word generates the address for the Hold-off Timer bank which then generates the
hold-off value for the channels. The channel that addressed the Modulation Word captures the 12-bit value
storing it in the channel Hold-off timer. In
channel CH0 is requesting access to the
Modulation Word thus receiving the hold-off value from the Hold-off Timer Bank. Each reaction channel
has its own internal hold-off timer.
23.4.5
Threshold bank and comparator
The Threshold bank and comparator contains the threshold levels to be compared against the ADC results.
This submodule also performs the comparison between the ADC result and the selected threshold value.
The Threshold bank can be programmed with up to 64 threshold values depending on the configuration
defined during the module integration.
An ADC result received from the on-chip ADC is connected to the ADC router and then to the comparator.
See
. This result stays at the comparator input until the Reaction Channel and Modulation
Control Word selects the address of the Threshold value. The THRESPT field in the Modulation Control
Word submodule is used as the address for the Threshold Bank. Note that if Threshold/Threshold
modulation mode is used two comparisons need to be executed with two different Threshold values. After
the first comparison is made the THRESPT pointer is incremented and a new comparison is done:
•
First comparison: COMP = ADC_DATA
THRESHOLD_VALUE[THRESPT]
•
Second comparison: COMP = ADC_DATA < THRESHOLD_VALUE[T 1]
The COMP (comparison result) is routed to the channel selected by the received TAG. Once having
received the comparison result the channel takes the appropriate actions in order to execute the modulation
mode as defined by the modulation control word.
TIMER
BANK
HOLD-OFF
HDOFFPT
Hold-off time value[11:0]
12
4
(to all Reaction channels)
CPU
Modulation
Control
hdt
hdt
hdt
CH0
CH1
CHn
16
Hold-off timer
Reaction Channels
Summary of Contents for MPC5644A
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Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...