C511 Datasheet, PDF (22/43 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

C511 / C513
Timer / Counter 2 (not available in the C511/C511A)
Timer 2 is a 16-bit Timer/Counter with up/down count feature. It can operate either as timer or as an
event counter which is selected by bit C/T2 (T2CON.1). It has three operating modes as shown in
table 8.
Table 8
Timer/Counter 2 Operating Modes
T2CON
Mode ^R×CLK
or
T×CLK
CP/
RL2
16-bit 0
0
Auto-
reload 0
0
0
0
0
0
16-bit 0
1
Cap-
ture
0
1
Baud 1
X
Rate
Gene-
rator
1
X
off
X
X
T2MOD T2CON
TR2
DCEN
P1.1/
T2EX
Remarks
EXEN
Input Clock
internal
external
(P1.0/T2)
1
0
1
0
1
1
1
1
1
X
1
X
1
X
1
X
0
X
0
X reload upon
overflow
1
↓
reload trigger
(falling edge)
f_OSC/12
max
f_OSC/24
X
0 Down counting
X
1 Up counting
0
X 16-bit Timer/
Counter (only
1
up-counting)
↓ capture TH2,
f_OSC/12
max
f_OSC/24
TL2 → RC2H,
RC2L
0
X no overflow
interrupt
1
↓
request (TF2)
extra external
f_OSC/2
max
f_OSC/24
interrupt
(“Timer 2”)
X
X Timer 2 stops
–
–
Note: ↓ =
falling edge
Semiconductor Group
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