atmega32c1 ATMEL Corporation, atmega32c1 Datasheet - Page 191

• Manufacturer Part Number: atmega32c1
• Description: Atmega32m1 Automotive 8-bit Avr Microcontroller With 32k/64k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

16.10.9
16.10.10 CAN Bit Timing Register 3 - CANBT3
7647A–AVR–02/08
CAN Bit Timing Register 2 - CANBT2
The period of the CAN controller system clock Tscl is programmable and determines the individ-
ual bit timing.
If ‘BRP[5..0]=0’, see
ple Point(s)” on page
• Bit 0 – Reserved Bit
This bit is reserved for future use. For compatibility with future devices, it must be written to zero
when CANBT1 is written.
• Bit 7– Reserved Bit
This bit is reserved for future use. For compatibility with future devices, it must be written to zero
when CANBT2 is written.
• Bit 6:5 – SJW1:0: Re-Synchronization Jump Width
To compensate for phase shifts between clock oscillators of different bus controllers, the control-
ler must re-synchronize on any relevant signal edge of the current transmission.
The synchronization jump width defines the maximum number of clock cycles. A bit period may
be shortened or lengthened by a re-synchronization.
• Bit 4 – Reserved Bit
This bit is reserved for future use. For compatibility with future devices, it must be written to zero
when CANBT2 is written.
• Bit 3:1 – PRS2:0: Propagation Time Segment
This part of the bit time is used to compensate for the physical delay times within the network. It
is twice the sum of the signal propagation time on the bus line, the input comparator delay and
the output driver delay.
• Bit 0 – Reserved Bit
This bit is reserved for future use. For compatibility with future devices, it must be written to zero
when CANBT2 is written.
Initial Value
Initial Value
Read/Write
Read/Write
Bit
Bit
7
7
-
-
-
-
-
-
Section 16.4.3 “Baud Rate” on page 175
192.
PHS22
SJW1
R/W
R/W
6
0
6
0
PHS21
SJW0
R/W
R/W
5
0
5
0
Tprs = Tscl x (PRS [2:0] + 1)
PHS20
R/W
4
4
0
-
-
-
Tscl =
Tsjw = Tscl x (SJW [1:0] +1)
PHS12
PRS2
R/W
R/W
3
0
3
0
clk
BRP[5:0] + 1
IO
frequency
PHS11
PRS1
R/W
R/W
ATmega32/64/M1/C1
2
0
2
0
and
PHS10
PRS0
R/W
R/W
1
0
1
0
Section • “Bit 0 – SMP: Sam-
SMP
R/W
0
0
0
-
-
-
CANBT2
CANBT3
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