Philips Semiconductors
Preliminary specification
80C51 8-bit microcontroller
8K/256 OTP, 8 channel 10 bit A/D, I2C, PWM,
capture/compare, high I/O, low voltage (2.7V–5.5V), low power
P87C552
Reset Value = 00H
7
6
5
4
3
2
1
0
IEN1 (E8H)
ET2
ECM2
ECM1
ECM0
ECT3
ECT2
ECT1
ECT0
(LSB)
(MSB)
BIT
SYMBOL FUNCTION
IEN1.7
IEN1.6
IEN1.5
IEN1.4
IEN1.3
IEN1.2
IEN1.1
IEN1.0
ET2
Enable Timer T2 overflow interrupt(s)
Enable T2 Comparator 2 interrupt
Enable T2 Comparator 1 interrupt
Enable T2 Comparator 0 interrupt
Enable T2 Capture register 3 interrupt
Enable T2 Capture register 2 interrupt
Enable T2 Capture register 1 interrupt
Enable T2 Capture register 0 interrupt
ECM2
ECM1
ECM0
ECT3
ECT2
ECT1
ECT0
SU01083
Figure 10. Timer T2 Interrupt Enable Register (IEN1)
Reset Value = 00H
7
6
5
4
3
2
1
0
TM2CON (EAH)
T2IS1
(MSB)
T2IS0
T2ER
T2BO
T2P1
T2P0 T2MS1 T2MS0
(LSB)
BIT
SYMBOL
FUNCTION
TM2CON.7
TM2CON.6
TM2CON.5
TSIS1
T2IS0
T2ER
Timer T2 16-bit overflow interrupt select
Timer T2 byte overflow interrupt select
Timer T2 external reset enable. When this bit is set,
Timer T2 may be reset by a rising edge on RT2 (P1.5).
TM2CON.4
TM2CON.3
TM2CON.2
T2BO
T2P1
T2P0
Timer T2 byte overflow interrupt flag
Timer T2 prescaler select
T2P1
T2P0
Timer T2 Clock
0
0
1
1
0
1
0
1
Clock source
Clock source/2
Clock source/4
Clock source/8
TM2CON.1
TM2CON.0
T2MS1
T2MS0
Timer T2 mode select
T2MS1 T2MS0
Mode Selected
0
0
1
1
0
1
0
1
Timer T2 halted (off)
T2 clock source = f
/12
OSC
Test mode; do not use
T2 clock source = pin T2
SU01084
Figure 11. T2 Control Register (TM2CON)
16
1999 Mar 30
NXP [ NXP ]
