Microcontroller not responding

[nikhilbaliga]

I am at a loss. I have tried everything

I am trying to transfer hex code from my computer into my microcontroller [Atmega16] through parallel port [DB25 - LPT1 port]

I am using Windows XP and Linux. I have used User Port and also dlportio.sys to unlock the port in Windows. I have made all the connections for transfer on a breadboard. I have used several transfer tools like AvrISP, PonyProg, AVRDUDE etc. to transfer the code. However in all the cases, I get the same (equivalent) error:

Ponyprog:
Device missing or unknown device (-24)

AVRISP:
Your target is not responding.

I have even changed the microcontroller because I thought my old one was not working. Still the same error. I have made continuity checks on the breadboard - all perfect. I have used resistances and also a buffer (wherever applicable). I have rechecked MOSI and MISO (not interchanged)

Please help ASAP

[Admin]

Can you tell us more about the device connecting between the DB25 connector and your AVR?

Are you sure you are on LPT1?

How are you powering your AVR?

[nikhilbaliga]

Yes, it is LPT1
I am using an eliminator [The variable DC supply] to power the chip

I read in the data sheet of atmega16 that the reset should be at 11.5 v to 12.5 volts while the VCC can be around 5 v. I have tried with all at 5v and also with the above mentioned scheme. Still nothing

I am using the standard DB25 cable - 25 pins and have drawn wires out of it at pins as mentioned below.
Parallel Port Pin num                      Atmega16 Pin
1                                                           8 - SCK
2                                                           6 - MOSI
11                                                         7 - MISO
16                                                         9 - RESET
20,21                                                    GND

[creedcradle]

Make sure that on your software tool is set on the LPT1 port, otherwise you will be getting the same generic message all over again...

Another thing, since you are using userport to unlock windows LPT port , you can try to physically test each bit of the PINS of your LPT port, on the Data PINS connect 680 resitor in series with a medium LED and the cathode end goes into the common ground. all of the data pins should be OFF. in this case you are sure that the LPT port is completely unlocked

hope this helps

[jsmoker]

Hmm, just want to make sure, but you know that pins 1 and 11 (and 14 and 17) are inverted so a 1 in software would be a 0 on the output.

[annoyin_kid]

i don't know anything about the ic that you are using but by any chance did you fry the ic? sparks, smoke and if the ic gets very warm is a bad sign.

[creedcradle]

Hmm, just want to make sure, but you know that pins 1 and 11 (and 14 and 17) are inverted so a 1 in software would be a 0 on the output.

I know it that is why i advised to do a bit test on data pins (2-9 PINs) only

windows XP for me is so dynamic, even on boot up it sends data to the LPT port, data PINS are mostly affected, so when using the userport software i used the data PINS to test if the port was unlocked completely

[garriwilson]

Do you have the AVRISP mkII? IF yes, then I had tons of problems too. However, I just played with the oscillator speed and luckily after 5 days it worked. Most importantly, DON'T GIVE UP!!!

If you have the cheap programmer then I can only leave it to the experts to help you because I've never worked with it. Sorry

[weiwei07]

hi, i m new here. Well normally here we use PIC to do our projects. What are the difference between a PIC and Atmega chip?

[creedcradle]

hi, i m new here. Well normally here we use PIC to do our projects. What are the difference between a PIC and Atmega chip?

Nice question! I bet several guys would reply your post! I hope it won't end with the question, which is better?(for sure it is a debate) 

[Ro-Bot-X]

This question has been asked before, do a search on the forum.

My opinion is: the difference is a matter of taste. In some places, like in my country, Romania, students at the university study PICs and 8051s. AVR is rather new, not so many examples and references. But this is changing fast, since more people chose AVRs for their projects since they are a little more powerfull than PICs. There are many microcontrollers based on PICs that offer you an easier way to work with them (integrated bootloader), like BasicSamp, Dios, Nemesis... Programing language is also a matter of taste. In the university they learn C because it is a more powerfull language than others. Basic is the beginner's choice, since it is easier to learn and powerfull enough for most projects. Java is another option, both PICs and AVRs have a interpreter with an integrated bootloader. So chose whatever you think you will be more comfortable to work with.