AT89LP216-20PI ATMEL [ATMEL Corporation], AT89LP216-20PI Datasheet - Page 33

• Manufacturer Part Number: AT89LP216-20PI
• Description: Microcontroller with 2K Bytes Flash
• Manufacturer: ATMEL [ATMEL Corporation]

14.5.1
14.5.2
3621A–MICRO–6/06
Mode 0 – 8-bit PWM with 8-bit Logarithmic Prescaler
Mode 1 – 8-bit PWM with 8-bit Linear Prescaler
In Mode 0, TLx acts as a logarithmic prescaler driving 8-bit counter THx (see
PSCx bits in TCONB control the prescaler value. On THx overflow, the duty cycle value in RHx
is transferred to OCRx and the output pin is set high. When the count in THx matches OCRx, the
output pin is cleared low. The following formulas give the output frequency and duty cycle for
Timer 0 in PWM Mode 0. Timer 1 in PWM Mode 0 is identical to Timer 0.
Figure 14-6. Timer/Counter 1 PWM Mode 0
In Mode 1, TLx provides linear prescaling with an 8-bit auto-reload from RLx (see
On TLx overflow, TLx is loaded with the value of RLx. THx acts as an 8-bit counter. On THx
overflow, the duty cycle value in RHx is transferred to OCRx and the output pin is set high. When
the count in THx matches OCRx, the output pin is cleared low. The following formulas give the
output frequency and duty cycle for Timer 0 in PWM Mode 1. Timer 1 in PWM Mode 1 is identi-
cal to Timer 0.
INT1 Pin
GATE
OSC
Mode 0:
Mode 1:
Mode 0:
Mode 1:
TR1
÷TPS
f
f
Duty Cycle %
Duty Cycle %
out
out
Control
=
=
Oscillator Frequency
------------------------------------------------------ -
Oscillator Frequency
------------------------------------------------------ -
256
256
PSC1
×
×
(
=
=
256
2
AT89LP216 [Preliminary]
PSC
100
100
(8 Bits)
TL1
–
0
RL
×
×
+
1
RH0
----------- -
RH0
----------- -
256
0
256
)
×
×
(8 Bits)
(8 Bits)
OCR1
RH1
TH1
------------------- -
TPS
------------------- -
TPS
1
1
+
=
+
1
1
Figure
Figure
14-6). The
T1
14-7).
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