Rainbow Electronics ATmega64M1 - Manual (Page 172)

172
8209A–AVR–08/09
ATmega16M1/32M1/64M1
The total number of TQ in a bit time has to be programmed at least from 8 to 25.
Figure 20-7. Sample and Transmission Point
Figure 20-8. General Structure of a Bit Period
Bit Timing
Sample
Point
Transmission
Point
Prescaler BRP
PRS (3-bit length)
SJW (2-bit length)
PHS1 (3-bit length)
PHS2 (3-bit length)
CLK
IO
Fcan (Tscl)
Time Quantum
Bit Rate Prescaler
CLK
IO
F
CAN
Data
Tscl (TQ)
1 /
CLK
IO
one nominal bit
Tsyns (5)
Tphs2+Tsjw ( 4 ) Tphs1+Tsjw ( 3 )
Tbit
Tphs2 ( 2 ) Tphs1 ( 1 ) Tprs
Sample
Point
Transmission
Point
5. Synchronization Segment: SYNS
Tsyns=1 x Tscl ( fixed )
Notes: 1. Phase error < 0
2. Phase error > 0
3. Phase error > 0
4. Phase error < 0
or or