C508_01 Datasheet, PDF (97/267 Pages) Infineon Technologies AG – 8-Bit CMOS Microcontroller

C508
On-Chip Peripheral Components
6.2.2.2 Timer 2 Operation
Timer 2, which is a 16-bit-wide register, operates as a timer with its count rate derived
from the oscillator frequency. A prescaler offers the possibility of selecting a count rate
of 1/3 or 1/6 of the oscillator frequency. Thus, the 16-bit timer register (consisting of TH2
and TL2) is either incremented in every machine cycle or in every second machine cycle.
The prescaler is selected by bit T2PS in special function register T2CON. lf T2PS is
cleared, the input frequency is 1/3 of the oscillator frequency. If T2PS is set, the 2:1
prescaler gates 1/6 of the oscillator frequency to the timer.
The timer overflow flag TF2 in SFR IRCON is set when there is a roll-over of the count
from all ‘1’s to all ‘0’s. The flag TF2 can generate an interrupt and it must be cleared by
the interrupt service routine.
User’s Manual
6-32
2001-05