Philips Semiconductors
CMOS single-chip 8-bit microcontrollers
Product specification
80C52/80C54/80C58
IE0 (A8H)
7
6
5
4
3
2
1
0
EA
—
ET2
ES
ET1 EX1 ET0 EX0
Enable Bit = 1 enables the interrupt.
Enable Bit = 0 disables it.
BIT
SYMBOL FUNCTION
IE.7
EA
Global disable bit. If EA = 0, all interrupts are disabled. If EA = 1, each interrupt can be individually
enabled or disabled by setting or clearing its enable bit.
IE.6
—
IE.5
ET2
Timer 2 interrupt enable bit.
IE.4
ES
Serial Port interrupt enable bit.
IE.3
ET1
Timer 1 interrupt enable bit.
IE.2
EX1
External interrupt 1 enable bit.
IE.1
ET0
Timer 0 interrupt enable bit.
IE.0
EX0
External interrupt 0 enable bit.
SU00743
Figure 10. IE Registers
IP0 (B8H)
7
6
5
4
3
2
1
0
—
—
PT2
PS
PT1 PX1 PT0 PX0
Priority Bit = 1 assigns high priority
Priority Bit = 0 assigns low priority
BIT
SYMBOL FUNCTION
IP.7
—
Not implemented, reserved for future use.
IP.6
—
IP.5
PT2
Timer 2 interrupt priority bit.
IP.4
PS
Serial Port interrupt priority bit.
IP.3
PT1
Timer 1 interrupt priority bit.
IP.2
PX1
External interrupt 1 priority bit.
IP.1
PT0
Timer 0 interrupt priority bit.
IP.0
PX0
External interrupt 0 priority bit.
Figure 11. IP Registers
SU00744
1996 Aug 16
17