Transmitting Message; Figure 5.2 Flowchart Of Message Transmission - Toshiba TXZ+ Series Reference Manual

5.2. Transmitting Message

Figure 5.2 shows an example flowchart of message transmission using the CANx transmission completion
interrupt (INTCANxTXD).
Setup a mailbox for
message transmission
Disable mailbox:
set [CANxMC]<MCn> to
Configure mailbox for
transmission:
set [CANxMC]<MDn> to
Setup mailbox identifier
and [CANxMBnID]<IDE> bit for
Standard ID
or extended ID
Choose transmission order:
setup [CANxMCR]<MTOS>
Enable interrupts:
set [CANxMBIM]<MBIMn> to
Enable mailbox:
set [CANxMC]<MCn> to
End of setup
It is also possible to use polling instead of transmission interrupts. In this case, the "waiting for INTCANxTXD" in
above flowchart must be replaced by polling [CANxTA]. Further, enabling interrupts and clearing [CANxMBTIF]
must be removed from the flow.
Yes New setup for
"0" the mailbox?
"0"
"1"
"1"

Figure 5.2 Flowchart of Message Transmission

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Transmitting messages
No
No
Update mailbox
data?
Yes
Write new data to the mailbox
Transmission
requested?
Yes
Set transmission request:
set [CANxTRS]<TRSn> to
Wait for
INTCANxTXD
Yes
Check [CANxTA]<TAn> to determine
the mailbox with <TAn> set
Special user tasks
(Update mailbox data?)
Clear [CANxTA]<TAn> and
[CANxMBTIF]<MBTIFn>
and return from interrupt
service routine
TXZ+ Family
CAN Controller
No
"1"
No
2020-10-01
Rev. 1.0