Keywords: AVR welding wire section (Fuse) forthright AVR Fuse bit MCU Fuse role AVR AVR Fuse

Avr fuse bits avr fuse avr melting silk weld wire atmega16 bits allocation melt silk weld wire bits set a fuse is what atmega128 welding wire Settings

AVR use fuse to control functions, such as the use of JTAG, clock, electrical testing voltage(BOD), whether to allow the commissioning etc.AVR Studio is the best way to modify avr fuses, JTAG and ISP can be used,and High-pressure programming also.

begin like the pictures show blow:

Using interface are as follows: (note: the following diagram,selected (ticked) means 0, unless means 1) said.

In order to use avr chips ,you must left at least one of JTAG or ISP enable, else the AVR chip is been locked ,you need to use High-pressure programming to programm it.

Examples of application:

As we want to use a piece of RC oscillation (namely inside need not pick crystals), can choose the choice of below:

• Int. RC Osc. 8 MHz; Start-up time: 6 CK + 0 ms;
• [CKSEL=0100 SUT=00] Int. RC Osc. 8 MHz; Start-up time: 6 CK + 4 ms;
• [CKSEL=0100 SUT=01] Int. RC Osc. 8 MHz; Start-up time: 6 CK + 64 ms; [CKSEL=0100 SUT=10]

As shown in figure: internal 1-m crystals, default typical Settings. (graph respectively for the fluctuation two parts, no part of the show is not selected state).

The following figure display is internal, 1 Mhz RC crystals

As we want to use external 7.3728 M crystals, can choose the choice of below:

• Ext. Crystal/Resonator High Freq.;
• Start-up time: 258 CK + 4 ms;
• [CKSEL=1110 SUT=00] or Ext. Crystal/Resonator High Freq;。

As follows: two 7.3728 M crystals (and typical melts silk of this development board of typical Settings) when using

Postscript: say something about Mega128 fuse

A series of avr ATmega128 is high, the design of the chip M103 mode, but this is compatible M103 pattern often harm. Based on this, the welding wire ATmega128, incidentally other function.

By default M103 mode is selected, should be removed; the Crystals, crystal oscillator is internal 1-m. If you use external crystals, should be amended. M128 can open hardware watchdog, select the watchdog, need not initialize program inside, you only need to feed your dog.

The first part of the default fuse

M103 compatible mode, can JTAG, enabling SPI, Bootloader area size, can make 4096 on.

The default fuse the second part

DOD to 2.7 V, internal 1-m crystals.

Below is the use of the website M128 development board M103 mode, the typical M128 mode, use external use, 7.3728 M crystals.

The first part of the typical welding wire (only said modification)

Remove the M103, which use M128 mode.

The second part of the typical welding wire

Keywords: AVR welding wire section (Fuse) forthright AVR Fuse bit MCU Fuse role AVR AVR Fuse

Avr fuse bits avr fuse avr melting silk weld wire atmega16 bits allocation melt silk weld wire bits set a fuse is what atmega128 welding wire Settings