W78c54 – Rainbow Electronics W78C54 User Manual
Page 10

W78C54
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Following tables show the interrupt informations and priority definitions.
Eight-source interrupt informations:
INTERRUPT
SOURCE
VECTOR
ADDRESS
POLLING
SEQUENCE WITHIN
PRIORITY LEVEL
ENABLE
REQUIRED
SETTINGS
INTERRUPT
TYPE
EDGE/LEVEL
External Interrupt 0
03H
0 (highest)
IE.0
TCON.IT0
Timer/Counter 0
0BH
1
IE.1
-
External Interrupt 1
13H
2
IE.2
TCON.IT1
Timer/Counter 1
1BH
3
IE.3
-
Serial Port
23H
4
IE.4
-
Timer/Counter 2
2BH
5
IE.5
-
External Interrupt 2
33H
6
XICON.EX2
XICON.IT2
External Interrupt 3
3BH
7 (lowest)
XICON.EX3
XICON.IT3
*Timer/Counter
***TL0, TH0, TL1, TH1, TL2, TH2, RCAP2L, RCAP2H
***TMOD - Timer 0, 1 mode (89H)
GATE
C//T
M1
M0
GATE
C//T
M1
M0
TIMER0
TIMER1
GATE: Gating control. When set, Timer/counter x is enabled only while INTx pin is high and TRx
control pin is set. When cleared, Timer x is enabled whenever the TRx conrol bit is set.
C//T:
Timer or Counter Selector. Cleared for timer operation. Set for counter operation.
M1 M0: Operating Mode
0 0: 13-bit Timer/Counter.
0 1: 16-bit Timer/Counter.
1 0: 8-bit auto-reload Timer/Counter. THx holds a value which is to be reloaded into TLx
each time it overflows.
1 1: Timer 0: TL0 is an 8-bit timer/counter controlled by the standard Timer 0 control bits.
TH0 is an 8-bit timer only controlled by Timer 1 control bits.
Timer 1: Timer/counter 1 stopped.
***TCON - Timer 0, 1 Control (88H)
TF1
TR1
TF0
TR0
IE1
IT1
IE0
IT0
TF1: Timer 1 overflow flag. Set by hardware on timer/counter overflow. cleared by hardware when
processor vectors to interrupt routine.