SAB80515 Datasheet, PDF (87/270 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller Family

On-Chip Peripheral Components
Figure 7-34
Special Function Register T2CON
0CFH 0CEH 0CDH 0CCH 0CBH 0CAH 0C9H 0C8H
0C8H T2PS I3FR I2FR T2R1 T2R0 T2CM T2I1 T2I0 T2CON
These bits are not used in combination with timer 2.
Timer 2 control register. Bit-addressable register which controls timer 2 function and compare mode
of registers CRC, CC1 to CC3.
Bit
T2I1
0
0
1
1
T2R1
0
1
1
T2CM
I3FR
T2PS
Symbol
T2I0
0
1
0
1
Timer 2 input selection
No input selected, timer 2 stops
Timer function
input frequency = f_OSC/12 (T2PS = 0) or f_OSC/24 (T2PS = 1)
Counter function, external input signal at pin T2/P1.7
Gated timer function, input controlled by pin T2/P1.7
T2R0 Timer 2 reload mode selection
X Reload disabled
0 Mode 0: auto-reload upon timer 2 overflow (TF2)
1 Mode 1: reload upon falling edge at pin T2EX/P1.5
Compare mode bit for registers CRC, CC1 through CC3. When set,
compare mode 1 is selected. T2CM = 0 selects compare mode 0.
External interrupt 3 falling/rising edge flag, also used for capture function
in combination with register CRC (see section 7.5.3).
If set, capture to register to CRC (if enabled) will occur on a positive
transition at pin P1.0/INT3/CC0. If I3FR is cleared, capture will occur on
a negative transition.
Prescaler select bit. When set, timer 2 is clocked in the "timer" or "gated
timer" function with 1/24 of the oscillator frequency.
T2PS = 0 gates f_OSC/12 to timer 2. T2PS must be 0 for the counter
operation of timer 2.
Semiconductor Group
87