ATMEGA128-16MN Atmel, ATMEGA128-16MN Datasheet - Page 109

• Manufacturer Part Number: ATMEGA128-16MN
• Description: MCU AVR 128KB FLASH 16MHZ 64QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA128-16MN

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 128KB (64K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-MLF®, 64-QFN
• Processor Series: ATMEGA128x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATSTK501 - ADAPTER KIT FOR 64PIN AVR MCUATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Timer/Counter
Prescaler
Special Function IO
Register – SFIOR
2467V–AVR–02/11
Figure 45. Prescaler for Timer/Counter0
The clock source for Timer/Counter0 is named clk
system clock clk
from the TOSC1 pin. This enables use of Timer/Counter0 as a Real Time Counter (RTC). When
AS0 is set, pins TOSC1 and TOSC2 are disconnected from Port C. A crystal can then be con-
nected between the TOSC1 and TOSC2 pins to serve as an independent clock source for
Timer/Counter0. The Oscillator is optimized for use with a 32.768kHz crystal. Applying an exter-
nal clock source to TOSC1 is not recommended.
For Timer/Counter0, the possible prescaled selections are: clk
clk
Setting the PSR0 bit in SFIOR resets the prescaler. This allows the user to operate with a pre-
dictable prescaler.
• Bit 7 – TSM: Timer/Counter Synchronization Mode
Writing the TSM bit to one activates the Timer/Counter Synchronization mode. In this mode, the
value that is written to the PSR0 and PSR321 bits is kept, hence keeping the corresponding
prescaler reset signals asserted. This ensures that the corresponding Timer/Counters are halted
and can be configured to the same value without the risk of one of them advancing during con-
figuration. When the TSM bit is written to zero, the PSR0 and PSR321 bits are cleared by
hardware, and the Timer/Counters start counting simultaneously.
Bit
Read/Write
Initial Value
T0S
TOSC1
/128, clk
clk
PSR0
CS00
CS01
CS02
AS0
I/O
TSM
R/W
T0S
7
0
I/O
/256, and clk
. By setting the AS0 bit in ASSR, Timer/Counter0 is asynchronously clocked
R
6
–
0
clk
T0S
T0S
R
5
–
0
/1024. Additionally, clk
Clear
R
4
–
0
TIMER/COUNTER0 CLOCK SOURCE
ACME
R/W
0
3
0
T0
. clk
10-BIT T/C PRESCALER
T0S
T0
PUD
clk
R/W
2
0
as well as 0 (stop) may be selected.
T0
is by default connected to the main
PSR0
R/W
1
0
T0S
/8, clk
PSR321
ATmega128
R/W
0
0
T0S
/32, clk
SFIOR
T0S
/64,
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