User Manual

88
T89C51AC2
Rev. B – 19-Dec-01
17.1 Register s Table 51. IEN0 Register
IEN0 (S:A8h)
Interrupt Ena ble Register
Rese t Value: 0000 0 000b
bit addressable
76543210
EA EC ET2 ES ET1 EX1 ET0 EX0
Bit
Number
Bit
Mnemonic Description
7EA
Enable All interrupt bit
Clear to disable all interrupts.
Set to enable all interrupts.
If EA=1, ea ch interrupt source is individually enabled or disabled by sett ing or
clearing its interrupt enable bit.
6EC
PCA Interrupt Enable
Clear to disable the PCA interrupt.
Set to enable the PCA interrupt.
5ET2
Timer 2 overflow interrupt Enable bit
Clear to disable timer 2 overflow interrupt.
Set to enable timer 2 overflow interrupt.
4ES
Serial port Enable bit
Clear to disable serial port interrupt.
Set to enable serial port interrupt.
3ET1
Timer 1 overflow interrupt Enable bit
Clear to disable timer 1 overflow interrupt.
Set to enable timer 1 overflow interrupt.
2EX1
External interrupt 1 Ena ble bit
Clear to disable external interrupt 1.
Set to enable external interrupt 1.
1ET0
Timer 0 overflow interrupt Enable bit
Clear to disable timer 0 overflow interrupt.
Set to enable timer 0 overflow interrupt.
0EX0
External interrupt 0 Ena ble bit
Clear to disable external interrupt 0.
Set to enable external interrupt 0.