ATMEGA644PV ATMEL [ATMEL Corporation], ATMEGA644PV Datasheet - Page 269

• Manufacturer Part Number: ATMEGA644PV
• Description: 8-bit Microcontroller with 16/32/64K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

23.5.2
8011D–AVR–02/07
Scanning the RESET Pin
Figure 23-4. General Port Pin Schematic Diagram
The RESET pin accepts 5V active low logic for standard reset operation, and 12V active high
logic for High Voltage Parallel programming. An observe-only cell as shown in
inserted for the 5V reset signal.
Figure 23-5. Observe-only Cell
See Boundary-scan
Description for Details!
Pxn
From System Pin
PUD:
PUExn:
OCxn:
ODxn:
IDxn:
SLEEP:
IDxn
PULLUP DISABLE
PULLUP ENABLE for pin Pxn
OUTPUT CONTROL for pin Pxn
OUTPUT DATA to pin Pxn
INPUT DATA from pin Pxn
SLEEP CONTROL
Previous
From
PUExn
Cell
ShiftDR
0
1
ClockDR
SLEEP
OCxn
ATmega164P/324P/644P
ODxn
D
FF1
SYNCHRONIZER
WDx:
RDx:
WRx:
RRx:
RPx:
CLK
D
L
Q
Q
Q
Next
I/O
Cell
To
:
D
WRITE DDRx
READ DDRx
WRITE PORTx
READ PORTx REGISTER
READ PORTx PIN
I/O CLOCK
PINxn
Q
Q
To System Logic
RESET
RESET
Q
Q
Q
Q
PORTxn
DDxn
CLR
CLR
D
D
CLK
PUD
WDx
RDx
WRx
RPx
RRx
I/O
Figure 23-5
269
is