ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 222

• Manufacturer Part Number: ATMEGA325-16AJ
• Description: 8-bit Microcontroller with In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Scanning the RESET Pin
222
ATmega325/3250/645/6450
Figure 102. 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 Fig-
ure 103 is inserted both for the 5V reset signal; RSTT, and the 12V reset signal;
RSTHV.
Figure 103. 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
PUExn
Previous
From
Cell
ShiftDR
0
1
SLEEP
OCxn
ClockDR
ODxn
SYNCHRONIZER
D
L
WDx:
RDx:
WRx:
RRx:
RPx:
WPx:
CLK
Q
Q
D
I/O
FF1
:
Q
D
WRITE DDRx
READ DDRx
WRITE PORTx
READ PORTx REGISTER
READ PORTx PIN
WRITE PINx REGISTER
I/O CLOCK
PINxn
Next
Cell
Q
Q
To
RESET
RESET
PORTxn
Q
Q
Q
Q
DDxn
CLR
CLR
D
D
To System Logic
RRx
CLK
PUD
WDx
RDx
RPx
1
0
I/O
2570A–AVR–09/04
WPx
WRx