TC1796
Peripheral Units (Vol. 2 of 2)
Controller Area Network (MultiCAN) Controller
User’s Manual
22-123
V2.0, 2007-07
MultiCAN, V2.0
22.6
TTCAN Scheduler
22.6.1
Overview
The message transmission and reception of the time-triggered part TTCAN is controlled
by a scheduler mechanism. This scheduler is based on the cycle time and delivers the
time marks. The time marks are defined by the time mark entries TMEx. Whenever a
time mark is reached, programmable actions (defined by scheduler memory instruction
entries INSTRxy) can take place. Typical instructions include, for example, starting the
transmission of a message, checking if a message has been received, opening or
closing arbitration windows, or generating interrupts.
Figure 22-30 Scheduler Overview
The instructions following a time mark are read by the scheduler until the next time mark
entry is found. Then, the instruction collection process is stopped until the next time mark
is reached.
Note: The time mark values in the scheduler entries must be in increasing order.
MCA05856
. . . . .
INSTRn0
TMEn
. . . . .
INSTR20
TME2
INSTR21
. . . . .
INSTR10
TME1
INSTR11
Scheduler Memory
TM n
16
Equal ?
REFM
16
....
Scheduler
Cycle
Control Unit
BCC
CSM
Scheduler
Addressing
Scheduler
Instruction
Unit
Update MSC
Update WTE
Transmit Triggers
ARB
Interrupts
Reference
Message
Trigger TRMCx
MUX