SH7205 Datasheet, PDF (1050/1904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series

Section 20 Controller Area Network (RCAN-TL1)
In case of Merged Arbitrating Window the slot for transmission goes from the Tx_Trig of the
Mailbox opening the Window (TTW = 10 bin) to the end to the TEW of the Mailbox closing the
Window (TTW = 11 bin).The TXPR can be modified at any time. RCAN-TL1 ensures the
transmission of Time Triggered messages is always scheduled correctly. However, in order to
guarantee the correct schedule, there are some important rules that are :
 TTT (Tx Trigger Time) can be modified during configuration mode.
 TTT cannot be set outside the range of Time_Ref, which specifies the length of basic cycle.
This could cause a scheduling problem.
 TXPR is not automatically cleared for periodic transmission. If a periodic transmission
needs to be cancelled, the corresponding TXCR bit needs to be set by the application.
• Example of Time Triggered System
The following diagram shows a simple example of how time trigger system works using RCAN-
TL1 in time slave mode.
CCR = 0
TTT24
TTT25
Mailbox-24 (Tx)
TTT26
TTT27
Mailbox-25 to 27 (Tx)
TTT28
TTT29
CCR = 1
Mailbox-25 to 27 (Tx)
Mailbox-28 (Tx)
CCR = 2
Mailbox-24 (Tx)
Mailbox-25 to 27 (Tx)
CCR = 3
Mailbox-25 to 27 (Tx)
CCR = 4
Mailbox-24 (Tx)
Mailbox-25 to 27 (Tx)
CCR = 5
Mailbox-25 to 27 (Tx)
Mailbox-28 (Tx)
CCR = 6
Mailbox-24 (Tx)
Mailbox-25 to 27 (Tx)
Mailbox-29 (Tx)
CCR = 7
Mailbox-25 to 27 (Tx)
time
reference
exclusive
window
merged arbitrating window
exclusive
window
Figure 20.22 Example of Time trigger system as Time Slave
arbitrating
window
Rev. 1.00 Mar. 25, 2008 Page 1018 of 1868
REJ09B0372-0100