ATmega48 Atmel Corporation, ATmega48 Datasheet - Page 290

• Manufacturer Part Number: ATmega48
• Manufacturer: Atmel Corporation

Specifications of ATmega48

• Flash (kbytes): 4 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 256
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

2545T–AVR–05/11
Figure 28-1. Parallel programming.
Note:
Table 28-11. Pin name mapping.
Table 28-12. Pin values used to enter programming mode.
Signal name in
programming mode
RDY/BSY
OE
WR
BS1
XA0
XA1
PAGEL
BS2
DATA
V
PAGEL
CC
XA1
XA0
BS1
Pin
- 0.3V < AV
CC
< V
{PC[1:0]: PB[5:0]}
RDY/BSY
CC
PAGEL
+12V
Pin name
BS1
XA0
XA1
BS2
Prog_enable[3]
Prog_enable[2]
Prog_enable[1]
Prog_enable[0]
WR
+ 0.3V, however, AV
OE
PD1
PD2
PD3
PD4
PD5
PD6
PD7
PC2
Symbol
PD1
PD2
PD3
PD4
PD5
PD6
RESET
XTAL1
GND
PD7
PC2
PC[1:0]:PB[5:0]
I/O
I/O
O
I
I
I
I
I
I
I
CC
should always be within 4.5V - 5.5V.
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)
AVCC
VCC
+4.5V - 5.5V
+4.5V - 5.5V
ATmega48/88/168
DATA
Value
0
0
0
0
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