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Semiconductor Group
121
Interrupt System
lf two or more requests of different priority levels are received simultaneously, the request of the
highest priority is serviced first. lf requests of the same priority level are received simultaneously,
an internal polling sequence determines which request is to be serviced first. Thus, within each
priority level there is a second priority structure determined by the polling sequence, as follows (see
figure 8-8):
– Within one pair the "left" interrupt is serviced first
– The pairs are serviced from top to bottom of the table.
Figure 8-7
Special Function Registers IP0 and IP1 (Address 0A9H and 0B9H)
Corresponding bit locations in both registers are used to set the interrupt priority level of an interrupt
pair.
Bit
Function
IP1.x
IP0.x
–
0
0
Set priority level 0 (lowest)
0
1
Set priority level 1
1
0
Set priority level 2
1
1
Set priority level 3 (highest)
Bit
Function
IP1.0/IP0.0
IE0/IADC
IP1.1/IP0.1
TF0/IEX2
IP1.2/IP0.2
IE1/IEX3
IP1.3/IP0.3
TF1/IEX4
IP1.4/IP0.4
RI + TI/IEX5
IP1.5/IP0.5
TF2 + EXF2/IEX6
These bits are not used for interrupt control.
WDTS
IP0.5
IP0.4
IP0.3
IP0.2
IP0.1
IP0.0
0A9H
IP0
–
–
IP1.5
IP1.4
IP1.3
IP1.2
IP1.1
IP1.0
0B9H
IP1
–
*
Summary of Contents for SAB 80515 Series
Page 9: ...Semiconductor Group 9 Introduction Figure 1 2 Block Diagram ...
Page 12: ...Semiconductor Group 12 Fundamental Structure Figure 2 1 Detailed Block Diagram ...
Page 18: ...Semiconductor Group 18 Central Processing Unit Figure 3 1 Fetch Execute Sequence ...
Page 73: ...Semiconductor Group 73 On Chip Peripheral Components Figure 7 25 A D Converter Block Diagram ...
Page 83: ...Semiconductor Group 83 On Chip Peripheral Components Figure 7 33 a Timer 2 Block Diagram ...
Page 215: ...Device Specifications Semiconductor Group 215 ...
Page 217: ...Device Specifications Semiconductor Group 217 Pin Configuration P LCC 68 ...
Page 219: ...Device Specifications Semiconductor Group 219 Logic Symbol ...
Page 226: ...Device Specifications Semiconductor Group 226 Figure 1 Block Diagram ...
Page 229: ...Device Specifications Semiconductor Group 229 Figure 2 Memory Address Spaces ...
Page 239: ...Device Specifications Semiconductor Group 239 Figure 4 Block Diagram of the A D Converter ...
Page 241: ...Device Specifications Semiconductor Group 241 Figure 5 Interrupt Request Sources ...
Page 242: ...Device Specifications Semiconductor Group 242 Figure 6 Interrupt Priority Level Structure ...