C509-L_97 Datasheet, PDF (206/290 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

Interrupt System
C509-L
7.2.2 Interrupt Priority Registers
The 19 interrupt sources of the C509-L are combined to six interrupt groups (see table 7-1). Each
of the six interrupt groups can be programmed to one of four priority levels by setting or clearing a
bit in the IP0 and IP1 priority registers. Further details about the interrupt priority structure are given
in chapter 7.3.
Special Function Register IP0 (Address A9H)
Special Function Register IP1 (Address B9H)
Reset Value : 00H
Reset Value : 0X000000B
MSB
LSB
Bit No. 7
6
5
4
3
2
1
0
A9H OWDS WDTS IP0.5 IP0.4 IP0.3 IP0.2 IP0.1 IP0.0 IP0
7
B9H PDIR
6
5
4
3
2
1
0
– IP1.5 IP1.4 IP1.3 IP1.2 IP1.1 IP1.0 IP1
Bit
IP1.x
IP1.x
The shaded bits are not used for interrupt purposes.
Function
Interrupt Priority level bits (x=0-5)
IP1.x
0
0
1
1
IP0.x
0
1
0
1
Function
Interrupt group x is set to priority level 0 (lowest)
Interrupt group x is set to priority level 1
Interrupt group x is set to priority level 2
Interrupt group x is set to priority level 3 (highest)
Semiconductor Group
7-10
1997-10-01