TS87C51RD2 ATMEL Corporation, TS87C51RD2 Datasheet - Page 40

• Manufacturer Part Number: TS87C51RD2
• Description: (TS8xC51Rx2) High Performance 8-bit Microcontroller
• Manufacturer: ATMEL Corporation

6.5
Figure 6-13. Interrupt Control System
40
Interrupt System
EXF2
INT0
INT1
P C A I T
AT/TS8xC51Rx2
TF0
TF1
TF2
RI
TI
Individual Enable
The TS80C51Rx2 has a total of 7 interrupt vectors: two external interrupts (INT0 and INT1),
three timer interrupts (timers 0, 1 and 2), the serial port interrupt and the PCA global interrupt.
These interrupts are shown in Figure 6-13.
WARNING: Note that in the first version of RC devices, the PCA interrupt is in the lowest priority.
Thus the order in INT0, TF0, INT1, TF1, RI or TI, TF2 or EXF2, PCA.
Each of the interrupt sources can be individually enabled or disabled by setting or clearing a bit
in the Interrupt Enable register (See Table 6-17.Table 6-18.). This register also contains a global
disable bit, which must be cleared to disable all interrupts at once.
Each interrupt source can also be individually programmed to one out of four priority levels by
setting or clearing a bit in the Interrupt Priority register (See Table 6-18.) and in the Interrupt Pri-
ority High register (See Table 6-19.). shows the bit values and priority levels associated with
each combination.
The PCA interrupt vector is located at address 0033H. All other vector addresses are the same
as standard C52 devices.
IE0
IE1
IPH, IP
3
0
3
0
3
0
3
0
3
0
3
0
3
0
Global Disable
High priority
interrupt
Interrupt
polling
sequence, decreasing from
high to low priority
Low priority
interrupt
4188E–8051–08/06