AT89LP51ED2-20AU Atmel, AT89LP51ED2-20AU Datasheet - Page 87

• Manufacturer Part Number: AT89LP51ED2-20AU
• Description: 8-bit Microcontrollers - MCU 64KB 20MHz 2.4V-5.5V
• Manufacturer: Atmel

Specifications of AT89LP51ED2-20AU

• Rohs: yes
• Core: 8051
• Processor Series: AT89x
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 20 MHz
• Program Memory Size: 64 KB
• Data Ram Size: 256 B
• On-chip Adc: Yes
• Operating Supply Voltage: 2.4 V to 5.5 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: TQFP-44
• Mounting Style: SMD/SMT
• Data Rom Size: 4 KB
• Interface Type: 2-Wire, SPI, UART
• Number Of Programmable I/os: 36
• Number Of Timers: 3
• Program Memory Type: Flash
• Factory Pack Quantity: 160

13.6.3
3714A–MICRO–7/11
Mode 2 – 8-bit Frequency Generator
Figure 13-7. Timer/Counter 1 PWM Mode 1
Timer n in PWM Mode 2 functions as an 8-bit Auto-Reload timer, the same as normal Mode 2,
with the exception that the output pin Tn is toggled at every TLn overflow (see
Figure 13-9 on page
used to output a square wave of varying frequency. THn acts as an 8-bit counter. The following
formula gives the output frequency for Timer n in PWM Mode 2.
Note:
Figure 13-8. Timer/Counter 1 PWM Mode 2
INT1 Pin
GATE1
In Fast Mode, TPS applies only when the TnX2 bits in CKCON0 are set. TPS always
applies in Compatibility Mode, therefore setting TnX2 in Compatibility Mode will halve
the output frequency.
CLK
INT1 Pin
GATE1
TR1
SYS
Mode 2:
88). Timer 1 in PWM Mode 2 is identical to Timer 0. PWM Mode 2 can be
CLK
TR1
÷TPS
SYS
AT89LP51RD2/ED2/ID2 Preliminary
Control
f
÷TPS
out
=
Control
------------------------------------------
2
×
(
256 THn
f
(8 Bits)
(8 Bits)
SYS
RL1
TL1
–
(8 Bits)
(8 Bits)
TH1
TL1
)
×
-------------------- -
TPS
(8 Bits)
(8 Bits)
OCR1
RH1
TH1
1
+
1
=
Figure 13-8
T1
T1
and
87