TC1796
Peripheral Units (Vol. 2 of 2)
Controller Area Network (MultiCAN) Controller
User’s Manual
22-124
V2.0, 2007-07
MultiCAN, V2.0
22.6.2
Scheduler Memory
The scheduler contains a memory block in which the time mark entries (TMEx) and the
scheduler instruction entries (INSTRnx) are stored. Each time mark entry can be
followed by a number of scheduler instructions. The scheduler memory is organized as
a 32-bit wide memory holding the 32-bit wide time mark entries and the 32-bit wide
scheduler instruction entries.
The total number of time mark entries and scheduler instruction entries that can be
stored is limited by the size of the scheduler memory. In the TC1796, the scheduler
memory has a size of 128 words (32-bits).
Figure 22-31 TTCAN Scheduler Memory
The last word address of the scheduler memory is reserved for the start pointer STPTR0.
The value written at this address determines the start location of the first entry for the
TTCAN node (= CAN node 0 in the TC1796). STPTR0 indicates how many 32-bit (word)
entries below SPTR0 the first time mark entry (TME1) is located.
When the basic cycle end entry BCE (with GM = 0) is read by the scheduler, it prepares
the next scheduler instructions (read from scheduler memory) starting again with TME1.
MCA05857
STPTR0 =
Start Pointer to the
first entry of each
Basic Cycle = TME1
STPTR0
BCE
. . . . .
INSTRnz
. . . . .
INSTRn0
TMEn
. . . . .
INSTR30
TME3
INSTR2y
. . . . .
INSTR20
TME2
INSTR21
INSTR1x
. . . . .
INSTR10
TME1
INSTR11
Scheduler Memory
Scheduler Entries
for TTCAN of
CAN Node 0
End Address
of the Scheduler
Memory