SH7760 Datasheet, PDF (816/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

Address
Bit
H'104 + N*32 13
12
11
10
9
8
7
6
Bit Name Description
NMC
New Message Control
When this bit is cleared to 0, the Mailbox of which
CANRXPR/CANRFPR bit is already set does not store the new
message but maintains the old one and sets the corresponding
CANUMSR bit. When this bit is set to 1, the Mailbox of which
CANRXPR/CANRFPR bit is already set overwrites with the
new message and sets the corresponding CANUMSR bit.
ATX
Automatic Transmission of Data Frame
When this bit is set to 1 and a Remote Frame is received into
the Mailbox, a Data Frame is transmitted from the same
Mailbox using the current contents of the message data by
setting the corresponding CANTXPR automatically. The
scheduling of transmission is still governed by CAN identifier.
In order to use this function, MBC[2:0] needs be programmed
to B’001.
Important : Note that when this function is used, the RTR bit
will never be set despite receiving a Remote Frame. When a
Remote Frame is received, the host CPU will be notified by the
corresponding CANRFPR set, however, as the HCAN2 needs
to transmit the current message as a Data Frame, the RTR bit
remains 0. If a mailbox is configured to receive Remote
Frames, then the RTR bit is overwritten by the received CAN
Frames.
DART
Disable Automatic Re-Transmission
When this bit is set, it disables the automatic re-transmission of
a message in the event of an error on the CAN bus or an
arbitration lost on the CAN bus. When this function is used, the
corresponding CANTXCR bit is automatically set at the start of
transmission. When this bit is cleared, the HCAN2 tries to
transmit the message as many times as required until it is
successfully transmitted or it is cancelled by CANTXCR.
MBC2
MBC1
MBC0
Mailbox Configuration
These bits configure the nature of each Mailbox as shown in
Table 22.3. When MBC is set to B’111, the Mailbox is inactive,
i.e., it does not receive or transmit a message regardless of
CANTXPR or other settings. The setting of MBC = 110 is
prohibited.

Reserved

The write value should always be 0. The read value is not
guaranteed.
Rev. 1.0, 02/03, page 766 of 1294