atmega32c1 ATMEL Corporation, atmega32c1 Datasheet - Page 176

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

16.4.4
16.4.5
16.5
16.5.1
176
Message Objects
ATmega32/64/M1/C1
Fault Confinement
Overload Frame
Number of MObs
Notes:
(c.f.
An overload frame is sent by setting an overload request (OVRQ). After the next reception, the
CAN channel sends an overload frame in accordance with the CAN specification. A status or
flag is set (OVRF) as long as the overload frame is sent.
Figure 16-9. Overload Frame
The MOb is a CAN frame descriptor. It contains all information to handle a CAN frame. This
means that a MOb has been outlined to allow to describe a CAN message like an object. The set
of MObs is the front end part of the “mailbox” where the messages to send and/or to receive are
pre-defined as well as possible to decrease the work load of the software.
The MObs are independent but priority is given to the lower one in case of multi matching. The
operating modes are:
This device has 6 MObs, they are numbered from 0 up to 5 (i=5).
5. Tsjw = (1 to 4) x Tscl = (SJW[1..0]+ 1) x Tscl
Section 16.7 “Error Management” on page
– Disabled mode
– Transmit mode
– Receive mode
– Automatic reply
– Frame buffer receive mode
1. The total number of Tscl (Time Quanta) in a bit time must be from 8 to 25.
2. PHS2[2..0] 2 is programmable to be
Instructions
OVRQ bit
OVFG bit
RXCDAN
TXCDAN
Ident "A"
Cmd
Setting OVRQ bit
Message Data "A"
≤
PHS1[2..0] and
181).
CRC
A
Interframe
≥
Resetting OVRQ bit
1.
Overload Frame
Overload Frame
7647A–AVR–02/08
Ident "B"