SAF-C164SM Infineon Technologies, SAF-C164SM Datasheet - Page 106

• Manufacturer Part Number: SAF-C164SM
• Description: 16-Bit CMOS Microcontroller
• Manufacturer: Infineon Technologies

The example shown below establishes 3 interrupt classes which cover 2 or 3 interrupt
priorities, depending on the number of members in a class. A level 6 interrupt disables
all other sources in class 2 by changing the current CPU level to 8, which is the highest
priority (ILVL) in class 2. Class 1 requests or PEC requests are still serviced, in this case.
In this way, the 24 interrupt sources (excluding PEC requests) are assigned to 3 classes
of priority rather than to 7 different levels, as the hardware support would do.
Table 5-6
ILVL
(Priority)
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
User’s Manual
3
X
X
X
X
X
X
X
Software Controlled Interrupt Classes (Example)
2
X
X
X
X
GLVL
1
X
X
X
X
0
X
X
X
X
Interpretation
PEC service on up to 8 channels
Interrupt Class 1
5 sources on 2 levels
Interrupt Class 2
9 sources on 3 levels
Interrupt Class 3
5 sources on 2 levels
No service!
5-16
Interrupt and Trap Functions
C164CM/C164SM
Derivatives
V1.0, 2002-02