C868_02 Datasheet, PDF (71/244 Pages) Infineon Technologies AG – 8 - Bit CMOS Microcontroller

C868
On-Chip Peripheral Components
RC2L/H. The underflow condition sets the TF2 flag and causes FFFF_H to be reloaded
into the T2L/H registers. A fresh down counting sequence is started and the timer/
counter counts down as in the previous counting sequence.
In this mode, bit EXF2 toggles whenever an overflow or an underflow condition is
detected. This flag, however, does not generate an interrupt request.
Note: In counter mode, if the reload via T2EX and the count clock T2 are detected
simultaneously the reload takes precedence over the count. The counter
increments its value with the following T2 count clock.
FFFF_H
(Down count reload)
EXF2
f_SYS 12
C/T2 = 0
C/T2 = 1
TR2
Pin
T2
Overflow
Underflow
T2L/H
Timer 2
OR
TF2
Interrupt
Com16p-abriat tor
RC2L/H
Pin
T2EX
Figure 4-7 Auto-Reload Mode (DCEN = 1)
User’s Manual
4-27
V 0.4, 2002-01