Electrical – Can not flash atmega328p with usbasp

atmega328patmel-studioprogrammerusbasp

My usbasp was working fine.I could burn programme to atmega328p.But last night i wanted to cahnge the clockspeed by clock_prescale_set ( clock_div_t x ).
after that it burned successfully and changed the clock speed.But I couldnot burn any new program.it shows this error massage in avr studio:

avrdude.exe: warning: cannot set sck period. please check for usbasp firmware update.

avrdude.exe: error: programm enable: target doesn't answer. 1

avrdude.exe: initialization failed, rc=-1
Double check connections and try again, or use -F to override
this check.

What is the problem and how to solve it?

Best Answer

Many potential issues:

You have changed the devider to 8 and now your Atmega is clocked 1MHz. You need to slow down your usbasp by the slowSCK jumper. It is possible also by the command line option -B x but unfortunately your usbasp firmware does not support it. You need another usbasp to flash the new software.
You have changed other fuse bits - for example you set the external clock source. Then you need to connect the clock from the other source to the Atmega clock pin.
I you have changed something else (for example the function of the reset pin) your uC is bricked and it can be only unbricked by using the high voltage programmer. You can build your own one (take a look here).

Related Solutions

Electronic – How to tell that USBasp is working

The error message you are seeing means that the chip is not responding to the "enable programming mode" command that the programmer is sending. Either you have got the connections wrong, or the programmer is sending the commands too quickly (programming frequency too high).

New AVR chips come configured to use the chip's internal oscillator as a clock source, with the CLOCKDIV8 ("divide clock frequency by 8") fuse set. This means that they run at 1MHz. The maximum programming frequency the chip supports is clock speed / 4, i.e. 250kHz. The USBASP defaults to 375kHz, which is too fast, so you need to slow it down.

You do this either by setting the "slow SCK" jumper of your USBASP, if it has one, or by using the avrdude -B option:

    avrdude -c usbasp -p m328p -B 5 -U flash:w:bootloader.hex:i

The number after the -B option selects the programming speed (specifically, the clock period, the inverse of the frequency, so higher numbers mean slower frequencies). If -B 5 doesn't work, try a higher number, like -B12 or even -B60.

Update: this line in the avrdude output suggests that your USBASP firmware version doesn't support the -B option, so you will need to use the jumper:

    avrdude: warning: cannot set sck period. please check for usbasp firmware update.

Electronic – USBasp programmer first firmware

You could program it before you solder it in, using a ZIF socket programmer. If making many of the board, then your supplier can program them for you. ZIF socket programmers are available for QFN and MFN packages.

Alternatively you can provide an ISP header on the PCB, or equivalent pads for pogo-pins to program in circuit. Using just pads for pins takes up much less board space.

If it's a one-off prototype and you have already soldered it onto the board, you can also solder bodge wires from the pins of the MCU to a loose ISP header.

Best Answer

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Electronic – How to tell that USBasp is working

Electronic – USBasp programmer first firmware

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