SAF-C164SM Infineon Technologies, SAF-C164SM Datasheet - Page 370

• Manufacturer Part Number: SAF-C164SM
• Description: 16-Bit CMOS Microcontroller
• Manufacturer: Infineon Technologies

Busoff Recovery Sequence
If the device goes busoff, it will set bit BOFF and bit INIT of its own accord, stopping all
bus activities. For the CAN module to take part in the CAN bus activities again, the bus-
off recovery sequence must be started by clearing the bit INIT (via software). After INIT
has been cleared, the module will then wait for 129 occurrences of Bus idle before
resuming normal operation.
At the end of the busoff recovery sequence, the Error Management Counters will be
reset. This will automatically clear bits BOFF and EWRN.
During the waiting time after the resetting of INIT each time a sequence of 11 recessive
bits has been monitored, a Bit0Error code is written to the Control Register, enabling
the CPU to determine whether the CAN bus is stuck at dominant or continuously
disturbed and to monitor the progress of the busoff recovery sequence.
Note: An interrupt can be generated when entering the busoff state if bits IE and EIE are
User’s Manual
set. The corresponding interrupt code in bitfield INTID is 01
The busoff recovery sequence cannot be shortened by setting or resetting INIT.
19-33
On-Chip CAN Interface
H
C164CM/C164SM
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Derivatives
V1.0, 2002-02