AT89LP216-20PU Atmel, AT89LP216-20PU Datasheet - Page 29

• Manufacturer Part Number: AT89LP216-20PU
• Description: MCU 8051 2K FLASH 20MHZ 16-PDIP
• Manufacturer: Atmel
• Series: 89LPr

Specifications of AT89LP216-20PU

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 14
• Program Memory Size: 2KB (2K x 8)
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2.4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-DIP (0.300", 7.62mm)
• Processor Series: AT89x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: UART, SPI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 14
• Number Of Timers: 2
• Operating Supply Voltage: 2.4 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: AT89ISP
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Details

14.3
14.4
3621E–MICRO–11/10
Mode 2 – 8-bit Auto-reload Timer/Counter
Mode 3 – 8-bit Split Timer
Mode 2 configures the Timer register as an 8-bit Counter (TL1) with automatic reload, as shown
in
TH1, which is preset by software. The reload leaves TH1 unchanged. Mode 2 operation is the
same for Timer/Counter 0.
Figure 14-3. Timer/Counter 1 Mode 2: 8-bit Auto-reload
Note:
Timer 1 in Mode 3 simply holds its count. The effect is the same as setting TR1 = 0. Timer 0 in
Mode 3 establishes TL0 and TH0 as two separate counters. The logic for Mode 3 on Timer 0 is
shown in
locked into a timer function (counting machine cycles) and takes over the use of TR1 and TF1
from Timer 1. Thus, TH0 now controls the Timer 1 interrupt. While Timer 0 is in Mode 3, Timer 1
will still obey its settings in TMOD but cannot generate an interrupt.
Mode 3 is for applications requiring an extra 8-bit timer or counter. With Timer 0 in Mode 3, the
AT89LP216 can appear to have three Timer/Counters. When Timer 0 is in Mode 3, Timer 1 can
be turned on and off by switching it out of and into its own Mode 3. In this case, Timer 1 can still
be used by the serial port as a baud rate generator or in any application not requiring an
interrupt.
Figure 14-4. Timer/Counter 0 Mode 3: Two 8-bit Counters
Note:
Figure
RH1/RL1 are not required by Timer 1 during Mode 2 and may be used as temporary storage
registers.
RH0/RL0 are not required by Timer 0 during Mode 3 and may be used as temporary storage
registers.
Figure
14-3. Overflow from TL1 not only sets TF1, but also reloads TL1 with the contents of
Mode 2:
14-4. TL0 uses the Timer 0 control bits: C/T, GATE, TR0, INT0, and TF0. TH0 is
INT0 Pin
GATE
T0 Pin
OSC
INT0 Pin
T1 Pin
GATE
Time-out Period
÷TPS
÷TPS
÷TPS
TR1
C/T = 0
C/T =1
C/T = 0
C/T = 1
=
Control
Control
Control
------------------------------------------------------ -
Oscillator Frequency
(
(8 Bits)
(8 Bits)
256 TH0
(8 Bits)
(8 Bits)
TH1
TL1
–
Reload
)
TF1
×
(
Interrupt
Interrupt
Interrupt
TPS
AT89LP216
+
1
)
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