Read interrupt identifier
START
case interrupt identifier
0x800 else 0x0000
Status Change
END
IFx command register [31:16] = 0x007F
Write Message Number to IF1/IF2 command register
(Transfer message to IF1/IF2 registers,
clear NewDat and IntPnd)
Read IF1/IF2 message control
NewDat = 1
Read data from IF1/IF2 Data A,B
EoB = 1
Next Message Number in this FIFO Buffer
Yes
No
Yes
No
Message interrupt
Interrupt Handling
Message Number = interrupt identifier
CAN Bit Timing
1566
SPRUHE8E – October 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
M3 Controller Area Network (CAN)
NOTE:
All message objects of a FIFO buffer needs to be read and cleared before the next batch of
messages can be stored. Otherwise true FIFO functionality cannot be guaranteed, since the
message objects of a partly read buffer will be re-filled according to the normal (descending)
priority.
Reading from a FIFO Buffer message object and resetting its NewDat bit is handled the same way as
reading from a single message object.
Figure 23-10. CPU Handling of a FIFO Buffer (Interrupt Driven)
23.12 CAN Bit Timing
The CAN supports bit rates between 1 kBit/s and 1000 kBit/s.
