ATmega16/32/64/M1/C1
16.5.2.2
Tx Data & Remote Frame
1. Several fields must be initialized before sending:
– Identifier tag (IDT)
– Identifier extension (IDE)
– Remote transmission request (RTRTAG)
– Data length code (DLC)
– Reserved bit(s) tag (RBnTAG)
– Data bytes of message (MSG)
2. The MOb is ready to send a data or a remote frame when the MOb configuration is set
(CONMOB).
3. Then, the CAN channel scans all the MObs in Tx configuration, finds the MOb having
the highest priority and tries to send it.
4. When the transmission is completed the TXOK flag is set (interrupt).
5. All the parameters and data are available in the MOb until a new initialization.
16.5.2.3
Rx Data & Remote Frame
1. Several fields must be initialized before receiving:
– Identifier tag (IDT)
– Identifier mask (IDMSK)
– Identifier extension (IDE)
– Identifier extension mask (IDEMSK)
– Remote transmission request (RTRTAG)
– Remote transmission request mask (RTRMSK)
– Data length code (DLC)
– Reserved bit(s) tag (RBnTAG)
2. The MOb is ready to receive a data or a remote frame when the MOb configuration is
set (CONMOB).
3. When a frame identifier is received on CAN network, the CAN channel scans all the
MObs in receive mode, tries to find the MOb having the highest priority which is
matching.
4. On a hit, the IDT, the IDE and the DLC of the matched MOb are updated from the
incoming (frame) values.
5. Once the reception is completed, the data bytes of the received message are stored
(not for remote frame) in the data buffer of the matched MOb and the RXOK flag is set
(interrupt).
6. All the parameters and data are available in the MOb until a new initialization.
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7647F–AVR–04/09
ATMEL [ ATMEL ]
