AT89LS52-16AU Atmel, AT89LS52-16AU Datasheet - Page 17

• Manufacturer Part Number: AT89LS52-16AU
• Description: IC MCU 8K FLASH 16MHZ 44-TQFP
• Manufacturer: Atmel
• Series: 89LSr

Specifications of AT89LS52-16AU

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: UART/USART
• Peripherals: WDT
• Number Of I /o: 32
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 4 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Processor Series: AT89x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: UART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 4 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: AT89ISP
• Minimum Operating Temperature: - 40 C
• Package: 44TQFP
• Device Core: 8051
• Family Name: 89LS
• Maximum Speed: 16 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Figure 11-1. Timer 2 in Clock-Out Mode
12. Programmable Clock Out
2601C–MICRO–06/08
(T2EX)
P1.0
P1.1
(T2)
A 50% duty cycle clock can be programmed to come out on P1.0, as shown in
pin, besides being a regular I/O pin, has two alternate functions. It can be programmed to input
the external clock for Timer/Counter 2 or to output a 50% duty cycle clock ranging from 61 Hz to
4 MHz (for a 16 MHz operating frequency).
To configure the Timer/Counter 2 as a clock generator, bit C/T2 (T2CON.1) must be cleared and
bit T2OE (T2MOD.1) must be set. Bit TR2 (T2CON.2) starts and stops the timer.
The clock-out frequency depends on the oscillator frequency and the reload value of Timer 2
capture registers (RCAP2H, RCAP2L), as shown in the following equation.
In the clock-out mode, Timer 2 roll-overs will not generate an interrupt. This behavior is similar to
when Timer 2 is used as a baud-rate generator. It is possible to use Timer 2 as a baud-rate gen-
erator and a clock generator simultaneously. Note, however, that the baud-rate and clock-out
frequencies cannot be determined independently from one another since they both use
RCAP2H and RCAP2L.
OSC
TRANSITION
DETECTOR
÷2
Clock-Out Frequency
EXEN2
C/T2 BIT
EXF2
TR2
=
------------------------------------------------------------------------------------ -
4 x [65536-(RCAP2H,RCAP2L)]
÷2
Oscillator Frequency
TIMER 2
INTERRUPT
(8-BITS)
RCAP2L RCAP2H
TL2
T2OE (T2MOD.1)
(8-BITS)
TH2
AT89LS52
Figure
11-1. This
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