FlexCAN Module
MPC5644A Microcontroller Reference Manual, Rev. 6
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Freescale Semiconductor
— Programmable bit rate up to 1 Mbit/s
— Content-related addressing
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Flexible Message Buffers (up to 64) of zero to eight bytes data length
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Each message buffer configurable as Rx or Tx, all supporting standard and extended messages
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Individual Rx Mask Registers per Message Buffer
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Includes either 1056 bytes (64 message buffers), 544 bytes (32 message buffers) or 288 bytes (16
message buffers) of RAM used for message buffer storage
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Includes either 256 bytes (64 message buffers), 128 bytes (32 message buffers) or 64 bytes (16
message buffers) of RAM used for individual Rx Mask Registers
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Full featured Rx FIFO with storage capacity for 6 frames and internal pointer handling
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Powerful Rx FIFO ID filtering, capable of matching incoming IDs against either 8 extended, 16
standard or 32 partial (8 bits) IDs, with individual masking capability
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Selectable backwards compatibility with previous FlexCAN version
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Programmable clock source to the CAN Protocol Interface, either bus clock or crystal oscillator
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Unused message buffer and Rx Mask Register space can be used as general purpose RAM space
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Listen only mode capability
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Programmable loop-back mode supporting self-test operation
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Programmable transmission priority scheme: lowest ID, lowest buffer number or highest priority
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Time Stamp based on 16-bit free-running timer
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Global network time, synchronized by a specific message
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Maskable interrupts
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Independent of the transmission medium (an external transceiver is assumed)
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Short latency time due to an arbitration scheme for high-priority messages
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Low power modes, with programmable wake up on bus activity
32.2.3
Modes of operation
The FlexCAN module has four functional modes: Normal Mode (User and Supervisor), Freeze Mode,
Listen-Only Mode and Loop-Back Mode. There are also two low power modes: Disable Mode and Stop
Mode.
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Normal Mode (User or Supervisor):
In Normal Mode, the module operates receiving and/or transmitting message frames, errors are
handled normally and all the CAN Protocol functions are enabled. User and Supervisor Modes
differ in the access to some restricted control registers.
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Freeze Mode:
It is enabled when MCR[FRZ] is asserted. If enabled, Freeze Mode is entered when MCR[HALT]
is set or when Debug Mode is requested at MCU level. In this mode, no transmission or reception
of frames is done and synchronicity to the CAN bus is lost. See
for
more information.
•
Listen-Only Mode:
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
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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...
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