ATMEGA165-16AI Atmel, ATMEGA165-16AI Datasheet - Page 58

• Manufacturer Part Number: ATMEGA165-16AI
• Description: IC AVR MCU 16K 16MHZ 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA165-16AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

2573G–AVR–07/09
Consider the clock period starting shortly after the first falling edge of the system clock.
The latch is closed when the clock is low, and goes transparent when the clock is high,
as indicated by the shaded region of the “SYNC LATCH” signal. The signal value is
latched when the system clock goes low. It is clocked into the PINxn Register at the suc-
ceeding positive clock edge. As indicated by the two arrows tpd,max and tpd,min, a
single signal transition on the pin will be delayed between ½ and 1½ system clock
period depending upon the time of assertion.
When reading back a software assigned pin value, a nop instruction must be inserted as
indicated in Figure 25. The out instruction sets the “SYNC LATCH” signal at the positive
edge of the clock. In this case, the delay tpd through the synchronizer is 1 system clock
period.
Figure 25. Synchronization when Reading a Software Assigned Pin Value
INSTRUCTIONS
SYSTEM CLK
SYNC LATCH
PINxn
r16
r17
out PORTx, r16
0x00
nop
t
pd
0xFF
ATmega165/V
in r17, PINx
0xFF
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