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Reaction Module (REACM)
MPC5644A Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
717
23.4
Functional description
The following sections describe the Reaction Module functionality.
The Reaction Module is designed to allow a closed feedback loop control over the driver load currents.
The load can be an injector for a direct injection system or an electromagnetic actuator for a robotized
transmission. In both cases it is expected that a solenoid will actually be the load. The module architecture
is based on shared resources submodules that can be used by all six reaction channels. Please refer to
for details about the module architecture. The Reaction Module comprises the following
internal submodules:
•
Reaction Channel
•
Modulation Control Word Bank
•
Shared Timer Bank
•
Hold-off Bank
•
Threshold Bank
The following sections describe each one of these submodules and their combined operation.
23.4.1
Reaction channel
The Reaction Channel is the core of the Reaction Module. Each channel controls three output pins and is
controlled by a Control finite state machine (FSM) that receives parameters to generate a modulated
waveform as well as the timer control window, usually provided by eTPU. The ADC interface indicates
to the channel that a new ADC result is available. If
activated
by the eTPU channel, the reaction channel
reads the Modulation Word which provides addresses for the Threshold Value bank, Shared Timer Bank
and Hold-off Timer Bank. The date provided by the Threshold Bank is compared with the incoming ADC
result. Based on that comparison the reaction channel state machine selects the values for the output pin
registers. The modulation only occurs if
activated
by the timer control signal, which can be generated by
eTPU, or can be controlled by software by writing to the SWMC, software modulation control bit, in the
Channel Configuration register. The MM and SM fields in the Modulation Word provide the Modulation
Mode and Sequencer Mode control, respectively.
describes the internal architecture of the
reaction channel and its interconnection with other submodules.
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
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...