P87C52 PHILIPS [NXP Semiconductors], P87C52 Datasheet - Page 9

• Manufacturer Part Number: P87C52
• Description: 80C51 8-bit microcontrollers 16K/32K, 512 OTP, I2C, watchdog timer
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
Additionally, if acting as master:
– generating START and STOP conditions
– handling bus arbitration
– generating serial clock pulses if S1BIT is not used.
Three SFRs control the bit-level I
S1SCS.
INTERRUPT SYSTEM
The interrupt structure of the 8XC528 is the same as that used in the
80C51, but includes two additional interrupt sources: one for the
third timer/counter, T2, and one for the I
enable and interrupt priority registers are IE and IP.
Table 3. Description of IE Bits
Table 4. Description of IP Bits
The interrupt vector locations and the interrupt priorities are:
Source
Vector
0003H
002BH
0053H
000BH
0013H
001BH
0023H
1999 Jul 23
MNEMONIC
MNEMONIC
80C51 8-bit microcontrollers
16K/32K, 512 OTP, I
ES1
ET2
ET1
EX1
ET0
EX0
PS1
PT2
PT1
PX1
PT0
PX0
EA
ES
PS
–
Address
IE0
TF2+EXF2
SI (I
TF0
IE1
TF1
RI+TI
2
C)
IE.7
IE.6
IE.5
IE.4
IE.3
IE.2
IE.1
IE.0
BIT
BIT
IP.7
IP.6
IP.5
IP.4
IP.3
IP.2
IP.1
IP.0
Priority within Level
Highest
Lowest
2
FUNCTION
General enable/disable control:
0 = NO interrupt is enabled.
1 = ANY individually enabled interrupt will be accepted.
Enable bit-level I
Enable Timer 2 interrupt
Enable Serial Port interrupt
Enable Timer 1 interrupt
Enable External interrupt 1
Enable Timer 0 interrupt
Enable External interrupt 0
FUNCTION
Reserved.
Bit-level I
Timer 2 interrupt priority level
Serial Port interrupt priority level
Timer 1 interrupt priority level
External Interrupt 1 priority level
Timer 0 interrupt priority level
External Interrupt 0 priority level
C interface: S1INT, S1BIT and
2
2
C, watchdog timer
C interface. The interrupt
2
C interrupt priority level
2
C I/O interrupt
9
IE: Interrupt Enable Register
This register is located at address A8H. Refer to Table 3.
IE SFR (A8H)
IP: Interrupt Priority Register
This register is located at address B8H. Refer to Table 4.
IP SFR (B8H)
EA
7
7
–
ES1
PS1
6
6
ET2
PT2
5
5
ES
PS
4
4
ET1
PT1
87C524/87C528
3
3
EX1
PX1
2
2
Product specification
ET0
PT0
1
1
EX0
PX0
0
0