Go Down

Topic: diy atmega8 arduino not uploading. please help! (Read 1 time) previous topic - next topic

spcomputing

No problem.

Also, you might want to put a 0.1uF from VCC-GND, AVCC-GND and AREF-GND close to the ATmega8.  It will help with high frequency noise devices can generate.

rene812

i made the changes u suggested. i now use the RST pin and added 0.1uf capacitors.
i am still no able to upload anything to the atmega8.

any idea what could be the cause of that?

spcomputing

I can not tell how the USB2UART is hooked up, but if the breakout board is silked correctly, it should be as follows:

3.3V - (Not connected)
RST - Atmega pin 1 thru 0.1uF cap
TX0 - Atmega pin 2 (RX0)
RX0 - Atmega pin 3 (TX0)
GND- Ground
5V  - Vcc

I see this USB2UART has a PWR and TX LED, is there any activity on the TX when you upload?

rene812

i tried it a couple of times like that but it's not working.
the USB2UART i'm using is slitchly different than the one in the link.
it is the one i ordered but apperently it has changed.
mine doesn't have a TX led.

spcomputing

Well that is unfortunate.  Lets try a manual reset.  When you press the upload button and the IDE compiles the sketch, press and hold the reset button down until the Binary Sketch Size: 1,234 bytes appears in the IDE window and then release the reset button.  There is a fussy timing of this, so a few tests may be needed (delaying release 100-500ms after the Binary Sketch Size).  Some people prefer just pressing it when the Binary Sketch Size appears.

It is a little easier with both RX and TX leds.

Go Up