Datasheet

76
4235K–8051–05/08
AT89C51RD2/ED2
Table 17-5. IPH0 Register
IPH0 - Interrupt Priority High Register (B7h)
Reset Value = X000 0000b
Not bit addressable
7 6 5 4 3 2 1 0
- PPCH PT2H PSH PT1H PX1H PT0H PX0H
Bit
Number
Bit
Mnemonic Description
7 -
Reserved
The value read from this bit is indeterminate. Do not set this bit.
6 PPCH
PCA interrupt Priority high bit.
PPCHPPCL Priority Level
0 0 Lowest
0 1
1 0
1 1Highest
5 PT2H
Timer 2 overflow interrupt Priority High bit
PT2HPT2L Priority Level
0 0Lowest
0 1
1 0
1 1Highest
4 PSH
Serial port Priority High bit
PSH PSLPriority Level
0 0Lowest
0 1
1 0
1 1Highest
3 PT1H
Timer 1 overflow interrupt Priority High bit
PT1HPT1L Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
2 PX1H
External interrupt 1 Priority High bit
PX1HPX1LPriority Level
0 0Lowest
0 1
1 0
1 1Highest
1 PT0H
Timer 0 overflow interrupt Priority High bit
PT0HPT0LPriority Level
0 0Lowest
0 1
1 0
1 1Highest
0 PX0H
External interrupt 0 Priority High bit
PX0H PX0LPriority Level
0 0Lowest
0 1
1 0
1 1Highest