ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 260

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

260
ATmega325/3250/645/6450
Figure 111. Parallel Programming
Table 112. Pin Name Mapping
Table 113. Pin Values Used to Enter Programming Mode
Programming Mode
Signal Name in
RDY/BSY
PAGEL
DATA
BS1
XA0
XA1
BS2
WR
OE
PAGEL
XA1
XA0
BS1
Pin
RDY/BSY
PAGEL
Pin Name
+12 V
BS2
BS1
XA0
XA1
WR
OE
PB7-0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PA0
I/O
I/O
PD1
PD2
PD3
PD4
PD5
PD6
PD7
RESET
XTAL1
GND
PA0
O
I
I
I
I
I
I
I
Prog_enable[3]
Prog_enable[2]
Prog_enable[1]
Prog_enable[0]
Symbol
Function
0: Device is busy programming, 1: Device is ready
for new command.
Output Enable (Active low).
Write Pulse (Active low).
Byte Select 1 (“0” selects low byte, “1” selects high
byte).
XTAL Action Bit 0
XTAL Action Bit 1
Program Memory and EEPROM data Page Load.
Byte Select 2 (“0” selects low byte, “1” selects 2’nd
high byte).
Bi-directional Data bus (Output when OE is low).
PB7 - PB0
AVCC
VCC
+5V
+5V
DATA
Value
0
0
0
0
2570A–AVR–09/04