W78ERD2 Datasheet, PDF (35/72 Pages) Winbond – 8-BIT MICROCONTROLLER

W78ERD2
9. INTERRUPT
INT2 / INT3
Two additional external interrupts, INT2 and INT3 , whose functions are similar to those of external
interrupt 0 and 1 in the standard 80C52. The functions/status of these interrupts are
determined/shown by the bits in the XICON (External Interrupt Control) register. The XICON register is
bit-addressable but is not a standard register in the standard 80C52. Its address is at 0C0H. To
set/clear bits in the XICON register, one can use the "SETB ( CLR ) bit" instruction. For example,
"SETB 0C2H" sets the EX2 bit of XICON.
Nine-source interrupt information
INTERRUPT SOURCE
External Interrupt 0
Timer/Counter 0
External Interrupt 1
Timer/Counter 1
Programmable
Counter Array
Serial Port
Timer/Counter 2
External Interrupt 2
External Interrupt 3
VECTOR
ADDRESS
03H
0BH
13H
1BH
33H
23H
2BH
33H
3BH
POLLING SEQUENCE
WITHIN PRIORITY
LEVEL
0 (highest)
1
2
3
4
5
6
7
8 (lowest)
ENABLE
REQUIRED
SETTINGS
IE.0
IE.1
IE.2
IE.3
IE.6
IE.4
IE.5
XICON.2
XICON.6
INTERRUPT TYPE
EDGE/LEVEL
TCON.0
-
TCON.2
-
-
-
-
XICON.0
XICON.3
Four-level interrupt priority
PRIORITY BITS
IPH.X
IP.X
0
0
0
1
1
0
1
1
INTERRUPT PRIORITY LEVEL
Level 0(lowest priority)
Level 1
Level 2
Level 3(highest priority)
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Publication Release Date: April 20, 2005
Revision A4