Mitsubishi Electric M32R Series User Manual page 651

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(6) ML (Message Lost) bit (D5)
This bit is effective for receive slots. It is set to 1 when the message slot contains unread receive
data which is overwritten by reception. This bit is cleared by writing a 0 in software.
(7) TRSTAT (Transmit/Receive Status) bit (D6)
This bit indicates that the CAN module is transmitting or receiving and is accessing the message
slot. This bit is set to 1 when the CAN module is accessing, and set to 0 when not accessing.
• For transmit slots
This bit is set to 1 when a transmit request for the message slot is accepted. It is cleared to 0
when the CAN module lost bus arbitration, when a CAN bus error occurs, or when
transmission is completed.
• For receive slots
This bit is set to 1 when during data reception, the received data is being stored in the message
slot. Note that the value read from message slot while TRSTAT bit remains set is
indeterminate.
(8) TRFIN (Transmit/Receive Finished) bit (D7)
This bit indicates that the CAN module finished transmitting or receiving.
• When set for transmit slots
This bit is set to 1 when the CAN module finished transmitting the data stored in the message
slot. This bit is cleared by writing a 0 in software. However, it cannot be cleared when TRSTAT
(Transmit/Receive Status) bit = 1.
• When set for receive slots
This bit is set to 1 when the CAN module finished receiving normally the data to be stored in
the message slot. This bit is cleared by writing a 0 in software. However, it cannot be cleared
when TRSTAT (Transmit/Receive Status) bit = 1.
Note 1: Before you can read received data from the message slot, you must clear the TRFIN
(Transmit/Receive Finished) bit. Note also that if the TRFIN (Transmit/Receive Finished)
bit is set to 1 after you read data, it means that new receive data was stored while you were
reading and the data you read contains an indeterminate value. In this case, discard the
read data, clear the TRFIN (Transmit/Receive Finished) bit, and read out data again.
Note 2: The TRFIN (Transmit/Receive Finished) bit has no effect for remote frames, so that it is not
set when remote frame transmission or reception is completed.
13.2 CAN Module Related Registers
13-37
CAN MODULE
Ver.0.10