AT90S8535-8AI Atmel, AT90S8535-8AI Datasheet - Page 32

• Manufacturer Part Number: AT90S8535-8AI
• Description: IC MCU 8K 8MHZ A/D IT 44TQFP
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S8535-8AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Timer/Counters
Timer/Counter
Prescalers
32
AT90S/LS8535
The AT90S8535 provides three general-purpose Timer/Counters – two 8-bit T/Cs and
one 16-bit T/C. Timer/Counter2 can optionally be asynchronously clocked from an exter-
nal oscillator. This oscillator is optimized for use with a 32.768 kHz watch crystal,
enabling use of Timer/Counter2 as a Real-time Clock (RTC). Timer/Counters 0 and 1
have individual prescaling selection from the same 10-bit prescaling timer.
Timer/Counter2 has its own prescaler. These Timer/Counters can either be used as a
timer with an internal clock time base or as a counter with an external pin connection
that triggers the counting.
Figure 28. Prescaler for Timer/Counter0 and 1
For Timer/Counters 0 and 1, the four different prescaled selections are: CK/8, CK/64,
CK/256 and CK/1024, where CK is the oscillator clock. For the two Timer/Counters 0
and 1, CK, external source and stop can also be selected as clock sources.
Figure 29. Timer/Counter2 Prescaler
TOSC1
CS20
CS21
CS22
AS2
CK
PCK2
TCK1
TIMER/COUNTER2 CLOCK SOURCE
0
10-BIT T/C PRESCALER
TCK2
TCK0
1041H–11/01