ATTINY87-SU Atmel, ATTINY87-SU Datasheet - Page 19

• Manufacturer Part Number: ATTINY87-SU
• Description: IC MCU AVR 8K FLASH 20SOIC
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY87-SU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, LIN, SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 16
• 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): 1.8 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SOIC (0.300", 7.50mm Width)
• Processor Series: ATtiny
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: 2-Wire, SPI, USI
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 2
• Operating Supply Voltage: 3.3 V, 5 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 125 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8265BS–AVR–09/10
3. ‘Disable Clock Source’ command remains enabled.
; (*) !!! Loose gain control of crystal oscillator !!!
; ==> WORKAROUND ...
; ...
In the Dynamic Clock Switch module, the ‘Disable Clock Source’ command remains run-
ning after disabling the targeted clock source (the clock source is set in the CLKSELR
register).
Problem fix / workaround.
After a ‘Disable Clock Source’ command, reset the CLKCSR register writing 0x80.
Code example:
; (*) !!! At this moment, if any other clock source is selected by
CLKSELR,
;
; ==> WORKAROUND ...
; Select watchdog clock ( 128KHz, fast rising power)
; Select crystal oscillator
; Disable clock source (crystal oscillator)
sts
ldi
sts
sts
ldi
sts
ldi
ldi
sts
sts
sts
this clock source will also stop !!!
CLKCSR,temp3
temp3,((0x03<<CSEL0)|(0x02<<CSUT0))
CLKSELR, temp3
CLKSELR, temp1
temp1,(0x0F<<CSEL0)
CLKSELR, temp1
temp2,(1<<CLKCCE)
temp3,(0x01<<CLKC0)
CLKCSR,temp2
CLKCSR,temp3
CLKCSR,temp2
; Clock source switch
; (*)
; CSEL = "0001"
; Enable CLKCSR register access
; (*) Disable crystal oscillator clock
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