Rainbow Electronics T89C51RD2 - Manual (Page 40)

40 Rev. F - 15 February, 2001
T89C51RD2
Table 20. IPH Register
IPH - 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 bit high.
PPCHPPC Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
5 PT2H
Timer 2 overflow interrupt Priority High bit
PT2HPT2 Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
4 PSH
Serial port Priority High bit
PSHPS Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
3 PT1H
Timer 1 overflow interrupt Priority High bit
PT1HPT1 Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
2 PX1H
External interrupt 1 Priority High bit
PX1HPX1 Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
1 PT0H
Timer 0 overflow interrupt Priority High bit
PT0HPT0 Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest
0 PX0H
External interrupt 0 Priority High bit
PX0HPX0 Priority Level
0 0 Lowest
0 1
1 0
1 1 Highest