AT89LP828 Atmel Corporation, AT89LP828 Datasheet - Page 49

• Manufacturer Part Number: AT89LP828
• Manufacturer: Atmel Corporation

Specifications of AT89LP828

• Flash (kbytes): 8 Kbytes
• Max. Operating Frequency: 25 MHz
• Cpu: 8051-1C
• Max I/o Pins: 30
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.75
• Eeprom (bytes): 1024
• Self Program Memory: IAP
• Operating Voltage (vcc): 2.4 to 5.5
• Timers: 3
• Isp: SPI/OCD
• Watchdog: Yes

11.5.3
3654A–MICRO–8/09
Mode 2 – 8-bit Frequency Generator
Figure 11-7. Timer/Counter 1 PWM Mode 1
Timer 0 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 T0 is toggled at every TL0 overflow (see
Figure 11-9 on page
used to output a square wave of varying frequency. THx acts as an 8-bit counter. The following
formula gives the output frequency for Timer 0 in PWM mode 2.
Figure 11-8. Timer/Counter 1 PWM Mode 2
Note:
INT1 Pin
GATE
{RH0 & RL0}/{RH1 & RL1} are not required by Timer 0/Timer 1 during PWM mode 2 and may be
used as temporary storage registers.
INT1 Pin
GATE
OSC
TR1
Mode 2:
TR1
50). Timer 1 in PWM mode 2 is identical to Timer 0. PWM mode 2 can be
OSC
÷TPS
Control
f
÷TPS
OUT
Control
=
Oscillator Frequency
------------------------------------------------------ -
2
×
(8 Bits)
(8 Bits)
(
RL1
256 TH0
TL1
–
(8 Bits)
(8 Bits)
TH1
TL1
)
×
(8 Bits)
(8 Bits)
OCR1
RH1
TH1
-------------------- -
TPS
AT89LP428/828
1
=
+
1
Figure 11-8
T1
T1
and
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