AT89S52
Figure 6. Timer 2 Auto Reload Mode (DCEN = 0)
÷12
OSC
C/T2 = 0
TH2
TL2
OVERFLOW
CONTROL
TR2
C/T2 = 1
RELOAD
T2 PIN
TIMER 2
INTERRUPT
RCAP2H RCAP2L
TF2
TRANSITION
DETECTOR
EXF2
T2EX PIN
CONTROL
EXEN2
Table 4. T2MOD – Timer 2 Mode Control Register
T2MOD Address = 0C9H
Not Bit Addressable
Reset Value = XXXX XX00B
–
7
–
6
–
5
–
4
–
3
–
2
T2OE
1
DCEN
0
Bit
Symbol
–
Function
Not implemented, reserved for future
Timer 2 Output Enable bit
T2OE
DCEN
When set, this bit allows Timer 2 to be configured as an up/down counter
11