Objective Development Forums

Re: atmega128

2010-09-07T13:55:13+02:00

Arxidatos wrote:I am newby at AVR and because i couldn't find an ATTINY45 i used an ATMEGA128 to test and practice with the code provided at CAPSLOCK project http://macetech.com/blog/?q=node/46. I used port D 2 for usb D- and port D 0 for usb D+ clocked into usbconfig.h with a 16MHz ceramic resonator the fuses WDTON 1,OCNED 1,JTAGEN 0,CKOPT 0, EESAVE 1, BOOTSZ1-2 0, BOOTRST 1, BODLEVEL 0, BOTEN 0, SUT1 1, SUT0 0, and all CKEL 1, initially the communication was not possible and was getting the message unknown device. after i solder into the interface circuit the 3V6 zeners all gone perfect. one more note for the timer TCCR1 use a 16bit value because for atmega128 this timer is 16bit.

I loved the project and the code excellent !!!

Hi Arxidatos, I want a small favour from you. please do help me.I am trying to emulate keyboard with Atmega128.People in forums where suggesting me to use 12MHz clock instead of 16MHz to make it work. As you are succesful in developing, please let me know if I have to change to 12MHz.Im a new bie in this field and im given a task to add this feature to the existing project .Please look at the link below.I dint start coding yet, planning to give for hardware desgning , requesting you to help asap. Thanks in advance.
http://img203.imageshack.us/img203/1061/schematict.jpg

Statistics: Posted by lucky5 — Tue Sep 07, 2010 1:55 pm

Re: atmega128

2010-02-10T01:19:29+02:00

I am newby at AVR and because i couldn't find an ATTINY45 i used an ATMEGA128 to test and practice with the code provided at CAPSLOCK project http://macetech.com/blog/?q=node/46. I used port D 2 for usb D- and port D 0 for usb D+ clocked into usbconfig.h with a 16MHz ceramic resonator the fuses WDTON 1,OCNED 1,JTAGEN 0,CKOPT 0, EESAVE 1, BOOTSZ1-2 0, BOOTRST 1, BODLEVEL 0, BOTEN 0, SUT1 1, SUT0 0, and all CKEL 1, initially the communication was not possible and was getting the message unknown device. after i solder into the interface circuit the 3V6 zeners all gone perfect. one more note for the timer TCCR1 use a 16bit value because for atmega128 this timer is 16bit.

I loved the project and the code excellent !!!

Statistics: Posted by Guest — Wed Feb 10, 2010 1:19 am

Re: atmega128

2009-07-25T09:56:02+02:00

Can someone send this file for sendspce or something that Guest gived (makefile.txt) pls?

Statistics: Posted by Guest — Sat Jul 25, 2009 9:56 am

atmega128

2007-04-10T16:07:52+02:00

At last, it works
I changed the fusebits to the values suggested, made no effect whatsoever. Then I pulled out the scope.

After plugging the chip to the scope, I noticed the USB signal was quite nasty, loads of round edges, no nice sharp edges. Plugging it into the ATMEGA16 revealed a nice signal with sharp edges. So now I knew it wasnt the chip itself, it was the hardware around it.

After replacing the pullup resistors and adding two 3V6 zener diodes I managed to get the signal right. After all it wasn't the chip itself, it proved to be other factors.

Thanks bigtime for the help and support

Statistics: Posted by Guest — Tue Apr 10, 2007 4:07 pm

atmega128

2007-04-09T09:38:02+02:00

Odd that changing the M103C fuse doesn't change the behavior.. Could you post the values of the three fuse bytes ? I would suggest these values:

Extended fuse byte -- 0xFF
High fuse byte -- 0xD9
Low fuse byte -- 0x9F

Also, what version of WinAVR are you using ? 20060421 or 20070122 ? (the latter is claimed to be "somewhat experimental"..)

Statistics: Posted by Grendel — Mon Apr 09, 2007 9:38 am

atmega128

2007-04-06T14:49:34+02:00

I've placed this statement:

XDIV = (0<
at the first line of my main-function. Following the datasheet this means that the clock divider is disabled, so the atmega128 runs at 12 mHz.

At this moment I don't have a scope or logic analyzer avaible. Tuesday, when I'm at school I can use one. I will post the results here, then.

@ Grendel, the Mega103 compatibility mode is disabled (bit unprogrammed). I've tried both options.

So, I don't have any succes yet.

Statistics: Posted by Guest — Fri Apr 06, 2007 2:49 pm

atmega128

2007-04-06T02:48:38+02:00

Hm, is the M103C fuse programmed (it is by default) ? If so, kill it.

Statistics: Posted by Grendel — Fri Apr 06, 2007 2:48 am

atmega128

2007-04-05T22:47:04+02:00

Interesting... Do you have any debug tools available such as a digital storage scope, a logic analyzer or at least a simple analog scope?

With a DSO, you should see a query/response dialog on D+, query and response being distinguished by slightly different voltage levels. Simple errors can usually be seen on the scope.

From the software side you might be able to see something with a USB snooper, but that assumes that there is at least SOME communication.

And another idea: The Mega128 has an XDIV register where you can divide the crystal frequency. Are you sure that this feature is disabled?

Statistics: Posted by christian — Thu Apr 05, 2007 10:47 pm

plukke

2007-04-05T21:51:34+02:00

Yes, I've changed the target to Atmega128. That's the only thing I've changed. I'va connected ecerything following the circuit that came with the zipfile PowerSwitch.2007-03-29.zip.

Here is a link to my makefile: makefile

( I've changed the extension to .txt so it could be downloaded. )

The only change is the device variable

Statistics: Posted by Guest — Thu Apr 05, 2007 9:51 pm

atmega128

2007-04-05T21:01:44+02:00

And are you sure you have changed the makefile to compile for the right target?

We have not tested AVR-USB with the ATMega128 yet, but I see no reason why it should not work. If there would be any address range problems, the compiler or assembler should print an error or at least a warning.

Statistics: Posted by christian — Thu Apr 05, 2007 9:01 pm