AT89C52-12AC ATMEL Corporation, AT89C52-12AC Datasheet - Page 8

• Manufacturer Part Number: AT89C52-12AC
• Description: 8-Bit Microcontroller with 8K Bytes Flash
• Manufacturer: ATMEL Corporation

Figure 3. Timer 2 Auto Reload Mode (DCEN = 1)
Figure 4. Timer 2 in Baud Rate Generator Mode
4-68
T2EX PIN
OSC
OSC
T2 PIN
÷
T2 PIN
12
÷
2
TRANSITION
DETECTOR
NOTE: OSC. FREQ. IS DIVIDED BY 2, NOT 12
AT89C52
C/T2 = 0
C/T2 = 1
C/T2 = 0
C/T2 = 1
TR2
EXEN2
TR2
CONTROL
CONTROL
CONTROL
(DOWN COUNTING RELOAD VALUE)
(UP COUNTING RELOAD VALUE)
RCAP2H
0FFH
TH2
RCAP2H
TH2
EXF2
RCAP2L
0FFH
TL2
RCAP2L
TL2
OVERFLOW
INTERRUPT
TIMER 2
T2EX PIN
÷
2
"1"
"1"
TIMER 1 OVERFLOW
COUNT
DIRECTION
1=UP
0=DOWN
"0"
"0"
"0"
TOGGLE
INTERRUPT
"1"
TIMER 2
÷
÷
TF2
SMOD1
RCLK
TCLK
16
16
CLOCK
CLOCK
EXF2
Rx
Tx