User`s guide

Sample Rate Transitions
7-15
As you can see from the preceding diagrams, Simulink can simulate models
with multiple sample rates in an efficient manner. However, Simulink does not
operate in real-time.
Slower to Faster Transitions in Real-Time
In models where a slower block drives a faster block, the generated code
assigns the faster block a higher priority than the slower block. This means the
faster block is executed before the slower block, which requires special care to
avoid incorrect results.
Figure 7-9: Time Overlaps in Slower to Faster transitions
t0 t1 t2 t3
T=1sT=2s
Time
FasterSlower
Block Block
T=1secT=2sec
T=2s
T=1s
T=1s T=1s
t0
t1
Time
T=2s
t2 t3 t4
1Sec
Task
21
1
2
The faster block executes a second time prior to the completion
of the slower block.
The faster block executes before the slower block.
Faster
Block Block
T=1secT=2sec
T=1s
T=1s
T=1s
T=1s
T=1s
T=2s
2Sec
Task
1
2
t0
t2