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  • atmega8 programming

    Hi
    Built this programmer to flash hex atmega 8 via ICSP on the minipulse 3 and my computer says theres drive missing.
    Using pony 2000
    Connected 5v via usb, lcd screen light comes on but thats it
    Have I done something wrong ?

    Tell you now im a novis far as programmers and programming

    Thanks in advance
    Dave
    Attached Files

  • #2
    I not checked exact minipulse ckt. but this (or similar) programmer works, just you need to apply power to minipulse first, (to get +5V), temporary remove any capacitor from RESET to GND, usually 100 nF or so, if installed on PCB, if pony calibration and correct COM port is selected, business done.(check configuration bits,"fuses", and program them correctly too)

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    • #3
      Checked that earlier the reset is wired directly to the isp pins together the rest of them, its just my computer doesnt see the atmega 8.
      Since my last post I built this to isolate the minipulse and still no result, im now wondering if its not my computer at fault so going to make a adaptor so i can feed it to lpt input on my old laptop as it hasnt a serial port.
      Another possibilty maybe got a couple of duff chips, but im doubtful of that although it wouldnt be a first.
      Has anybody used this setup on windows vista or 7? because ive tryed both.
      Im a bit peed off because this should be the easy part of the project.

      Regards
      Attached Files

      Comment


      • #4
        Heres the connections on the minipulse 3 using a 8mhz crystal instead of 4which shouldnt make any difference to the programming unless im wrong, used 25pf caps, that also should be ok, again correct me if im wrong.
        Theres alot to be said for analog, if i cant fire this project up in the next few days the whole lots going stright out the window, and that wont be a first either
        Right can you bright boys tell me where to scope the outputs from my computer serial port, I need to know whats not happening so i can get a picture in my brain of how its not working.
        There must be away of putting a dummy load on the end of the serial port to see imformation flowing.

        Regards
        Attached Files

        Comment


        • #5
          sorry about that even your eyes ant that good
          While looking at this circuit can anyone tell me what is the purpose of link J which is a 5v to contrast.

          Many thanks in advance
          Attached Files

          Comment


          • #6
            While I have not burned a at8 yet. What is the part number on your AT8

            I have had good luck with this setup
            http://www.geotech1.com/forums/showp...6&postcount=12

            The bascom programmer is only 4 resistors, I used an external 5v to the chip .
            what power connections did you use when burning the chip ?

            Also those LCD display's can be a pain to get going, I have found a 20k pot from ground to pin 3 the best way, they seem to need almost a full ground on pin 3 to get the contrast working

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            • #7
              Just as well show you the main circuit while im at it.
              Soon as its up and running and if its any good will be doing a full project on this with a few of my finer refinements on a brand new thread.
              Attached Files

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              • #8
                There should be pulses on pb1, which looks like pin 15.

                Comment


                • #9
                  Originally posted by 6666 View Post
                  While I have not burned a at8 yet. What is the part number on your AT8

                  I have had good luck with this setup
                  http://www.geotech1.com/forums/showp...6&postcount=12

                  The bascom programmer is only 4 resistors, I used an external 5v to the chip .

                  Also those LCD display's can be a pain to get going, I have found a 20k pot from ground to pin 3 the best way, they seem to need almost a full ground on pin 3 to get the contrast working
                  Firstly thats a good bit of sound advise if it will burn a tiny should burn a atmega part of the same family by what I can tell
                  The chip number is ATMEGA8-16PU
                  Its 8 bit 8k MCU DR 28 bought from farnells.
                  The LCD im using is HJ1 602A which works on 3.2v so series 3 in4007 diodes in series from the 5v supply.
                  That bascom programmer I was going to build but it looked to easy, thought it wouldnt work, just goes to show doesnt it.
                  Anymore feedback id be so greatfull.
                  Thanks again

                  Comment


                  • #10
                    Originally posted by 6666 View Post
                    There should be pulses on pb1, which looks like pin 15.
                    Would that be pulses while burning or after its programed?

                    Comment


                    • #11
                      Originally posted by satdaveuk View Post
                      Would that be pulses while burning or after its programed?

                      After its programed and the fuses burned, there should be pulses coming out of it.

                      Comment


                      • #12
                        That bascom programmer I was going to build but it looked to easy, thought it wouldnt work, just goes to show doesnt it.
                        Yes it looks too easy, but I tried some of the more complex ones and they did not work
                        works fine from the parallel port and a one metre cord, make sure ALL the wires in the cord
                        work, some cords have missing wires.
                        One other thing, while I am not expert on the AT8, I would probably try powering pins 7/8 and 20 21 22 while burning.

                        Here is the whole system.
                        Attached Files

                        Comment


                        • #13
                          The chip 74LS245 came in this morning already made the pcb so shall build this, theres engineers on another forum used this build to directly program the minipulse 3 whilst chip is still in circuit getting the 5v by simply turning the detector on which is what ive been trying to do in the first place, anyway it remains to be seen, if it doesnt work then shall try your idea, got breadboard but never ever used it still in the box, maybe about time I did which will make it the 4th build all just to program a poxy chip after that shall build back up a old DEL computer I have in the workshop and load windows 98se which is what I used to flash TV chips in the old days stright from the serial port, Got a sneeky feeling that thats where the problem lies.
                          Good advise from you checking the leads although already done continuty checks worth a second look, what a bummer that would be if it was simple as that.

                          Regards
                          Attached Files

                          Comment


                          • #14
                            parts list

                            If some of you fancy doing a sim on the minipulse3 heres the parts lists, need to look at both sheets, starts off a bit confusing to build but then it all clicks if you get my meaning.
                            I used all parts from the pdf file which far as I know is the most uptodate where applicable apart from U12 which as you know used the atmega 8.
                            Theres not many people had good results with this design but weeded out a few thats had excellent results

                            Regards
                            Attached Files

                            Comment


                            • #15
                              Just for fun I have ordered a ATMEGA8-16PU and some 8 meg xtals
                              they will take a few days to arrive, then will try and burn the chip
                              and see what happens

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