C515A_9708 Datasheet, PDF (78/182 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

On-Chip Peripheral Components
C515A
Special Function Register IEN0 (Address A8H)
Special Function Register IEN1 (Address B8H)
Special Function Register IRCON (Address C0H)
MSB
Bit No. AF_H
AE_H
AD_H
AC_H
AB_H AA_H
A8H EAL WDT ET2 ES ET1 EX1
A9_H
ET0
Reset Value : 00H
Reset Value : 00H
Reset Value : 00H
LSB
A8_H
EX0 IEN0
Bit No. BF_H BE_H
B8H EXEN2 SWDT
BD_H
EX6
BC_H
EX5
BB_H
EX4
BA_H
EX3
B9_H B8_H
EX2 EADC
IEN1
Bit No.
C0H
C7_H
EXF2
C6_H C5_H
TF2 IEX6
C4_H C3_H C2_H
IEX5 IEX4 IEX3
C1_H C0_H
IEX2 IADC
IRCON
The shaded bits are not used in timer/counter 2 interrupt control.
Bit
ET2
EXEN2
EXF2
TF2
Function
Timer 2 overflow / external reload interrupt enable.
If ET2 = 0, the timer 2 interrupt is disabled.
If ET2 = 1, the timer 2 interrupt is enabled.
Timer 2 external reload interrupt enable
If EXEN2 = 0, the timer 2 external reload interrupt is disabled.
If EXEN2 = 1, the timer 2 external reload interrupt is enabled. The external reload
function is not affected by EXEN2.
Timer 2 external reload flag
EXF2 is set when a reload is caused by a falling edge on pin T2EX while EXEN2 =
1. If ET2 in IEN0 is set (timer 2 interrupt enabled), EXF2 = 1 will cause an interrupt.
EXF2 can be used as an additional external interrupt when the reload function is
not used. EXF2 must be cleared by software.
Timer 2 overflow flag
Set by a timer 2 overflow and must be cleared by software. If the timer 2 interrupt
is enabled, TF2 = 1 will cause an interrupt.
Semiconductor Group
6-27
1997-08-01