ATmega168A Atmel Corporation, ATmega168A Datasheet - Page 305

no-image

ATmega168A

Manufacturer Part Number
ATmega168A
Description
Manufacturer
Atmel Corporation
Datasheets

Specifications of ATmega168A

Flash (kbytes)
16 Kbytes
Pin Count
32
Max. Operating Frequency
20 MHz
Cpu
8-bit AVR
# Of Touch Channels
16
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
Yes
Crypto Engine
No
Sram (kbytes)
1
Eeprom (bytes)
512
Self Program Memory
YES
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
Table 28-16. Command Byte Bit Coding
Command Byte
0000 1000
0000 0100
0000 0010
0000 0011
28.7
Parallel Programming
28.7.1
Enter Programming Mode
The following algorithm puts the device in Parallel (High-voltage) Programming mode:
1. Set Prog_enable pins listed in
V
CC
2. Apply 4.5 - 5.5V between V
Ensure that V
3. Wait 20 - 60 µs, and apply 11.5 - 12.5V to RESET.
4. Keep the Prog_enable pins unchanged for at least 10µs after the High-voltage has been
applied to ensure the Prog_enable Signature has been latched.
5. Wait at least 300 µs before giving any parallel programming commands.
6. Exit Programming mode by power the device down or by bringing RESET pin to 0V.
If the rise time of the V
tive algorithm can be used.
1. Set Prog_enable pins listed in
V
CC
2. Apply 4.5 - 5.5V between V
3. Monitor V
4. Keep the Prog_enable pins unchanged for at least 10µs after the High-voltage has been
applied to ensure the Prog_enable Signature has been latched.
5. Wait until V
commands.
6. Exit Programming mode by power the device down or by bringing RESET pin to 0V.
28.7.2
Considerations for Efficient Programming
The loaded command and address are retained in the device during programming. For efficient
programming, the following should be considered.
• The command needs only be loaded once when writing or reading multiple memory locations.
• Skip writing the data value 0xFF, that is the contents of the entire EEPROM (unless the
EESAVE Fuse is programmed) and Flash after a Chip Erase.
• Address high byte needs only be loaded before programming or reading a new 256 word
window in Flash or 256 byte EEPROM. This consideration also applies to Signature bytes
reading.
8271D–AVR–05/11
ATmega48A/PA/88A/PA/168A/PA/328/P
Command Executed
Read Signature Bytes and Calibration byte
Read Fuse and Lock bits
Read Flash
Read EEPROM
Table 28-14 on page 304
to 0V.
and GND.
CC
reaches at least 1.8V within the next 20 µs.
CC
is unable to fulfill the requirements listed above, the following alterna-
CC
Table 28-14 on page 304
to 0V.
and GND.
CC
, and as soon as V
reaches 0.9 - 1.1V, apply 11.5 - 12.5V to RESET.
CC
CC
actually reaches 4.5 -5.5V before giving any parallel programming
CC
to “0000”, RESET pin to 0V and
to “0000”, RESET pin to 0V and
305

Related parts for ATmega168A