Renesas R5S72622 Manual Do Utilizador

 

Section 20   Controller Area Network 

 

R01UH0134EJ0400  Rev. 4.00  

 

Page 1069 of 2108 

Sep 24, 2014 

 

 

 
SH7262 Group, SH7264 Group 

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. This module 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 this 
module in time slave mode. 

TTT24

TTT25

TTT26

TTT27

TTT28

TTT29

CCR = 0

Mailbox-24 (Tx)

Mailbox-28 (Tx)

Mailbox-28 (Tx)

Mailbox-29 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-25 to 27 (Tx)

Mailbox-24 (Tx)

Mailbox-24 (Tx)

Mailbox-24 (Tx)

time

reference

exclusive

window

exclusive

window

merged arbitrating window

arbitrating 

window

CCR = 1

CCR = 2

CCR = 3

CCR = 4

CCR = 5

CCR = 6

CCR = 7