ATMEGA161L-4PC Atmel, ATMEGA161L-4PC Datasheet - Page 86

• Manufacturer Part Number: ATMEGA161L-4PC
• Description: IC AVR MCU 16K LV 4MHZ COM 40DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA161L-4PC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 35
• 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
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Data Converters: -

86
ATmega161(L)
Figure 49. External Memory with Page Select
Figure 50. External Data Memory Cycles without Wait State (SRWn1 = 0 and SRWn0
=0)
Note:
Data/Address [7..0]
Data/Address [7..0]
(1)
System Clock Ø
Address [15..8]
1. SRWn1 = SRW11 (upper page) or SRW01 (lower page), SRWn0 = SRW10 (upper
page) or SRW00 (lower page).
The ALE pulse in period T4 is only present if the next instruction accesses the RAM
(internal or external). The Data and Address will only change in T4 if ALE is present
(the next instruction accesses the RAM).
ALE
WR
RD
Prev. addr.
Prev. data
Prev. data
External Memory
(0-63K x 8)
T1
XX
XX
XX
Address
Address
Internal memory
Data Memory
Lower page
Upper page
SRW01
SRW00
SRW11
SRW10
T2
XX
Address
Data
Data
$0000
$0460
$FFFF
SRL[2..0]
T3
T4
1228D–AVR–02/07
XX
XX
XX