AT89C52-20QC Atmel, AT89C52-20QC Datasheet - Page 9

• Manufacturer Part Number: AT89C52-20QC
• Description: Microcontrollers (MCU) Microcontroller
• Manufacturer: Atmel

Specifications of AT89C52-20QC

• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 8 KB
• Data Ram Size: 256 B
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Package / Case: PQFP-44
• Minimum Operating Temperature: 0 C
• Lead Free Status / Rohs Status: No

Figure 3. Timer 2 Auto Reload Mode (DCEN = 1)
Figure 4. Timer 2 in Baud Rate Generator Mode
T2EX PIN
OSC
OSC
T2 PIN
÷
T2 PIN
12
÷
2
TRANSITION
DETECTOR
NOTE: OSC. FREQ. IS DIVIDED BY 2, NOT 12
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
"1"
INTERRUPT
TIMER 2
÷
TF2
÷
SMOD1
RCLK
TCLK
16
16
CLOCK
CLOCK
EXF2
Rx
Tx
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