ACA 500+ DONT BOOT

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Don't Panic. Please wash hands.
  • Hallo ,

    I bought from ebay a used ACA500+ and try it tomy a500+ It comes with a black screen and sometimes a strange red or blue garbled screen and system is halted. The digits are showing after5 seconds 0_ and the last underscore _ is blinking.... The switch button has no effect.

    What can I do ? I think it has lost the firmware but it cant boot to reflash it. Is there any way to reprogram it from jtag or remove the chip put in a programer and reflash it or from elsewhere ? what else can I do?

    The switch had a problem and I replace it. I dont have a receipt and no waranty only the ebay buy. the only serial I have is ACA500plus ]142[ TT04W

    I can check whatever you told me with a multimeter or an osciloscope.

    Thank you.

  • That card has a history; it was sent in for "warranty repair" in summer 2017, and we found that it was inserted upside-down. I did repair the card to ultimately find out if my assumption about the customer was right - and it was. He was informed that the card was repaired, but not the Dismo, on august 17th, 2017. So the person knowingly sold you a defective card.


    For the record: The person in question has been blacklisted here. I don't want to do business with dishonest persons, even if it means less money in my pocket. I suggest that you demand your money back.

  • Dear sirs,

    Thank you for your reply. I bought the card as a defective one so I knew she has problems, and the price was low. Can we try to repair the card ? Either replacing the dismo or whatever solution you are thinking ? Is it possible to send it to you for repair ? I can test whatever you want and send pictures if you want.

    Thank you.:)

  • That card is "more than out of warranty" - I refuse to deal with it. Sorry, but with that history, there is no way I will spend any more time with it.

  • This card has a new good owner. I don’t want anything free of charge or in a warranty. I just want to pay for repairing this card and also all the shipping costs is on me. It’s a pity, to throw it away, her optical condition is good, and I think she needs only a reflashing and it will be ok. I am sure you can fix it! Please Jens, give us a chance contacting me through my email sending me the payment details including the shipment address.

    Thank you!

  • Re-flashing won't do it for the DisMo: There are two ICs on it that are dead. Further, given the behaviour of the original owner, there is reason to believe that it has not been treated "ideal", so just replacing the DisMo is risky, as the new one may suffer damage if the base card has been damaged the same way as it was originally.


    I've spent several hours with this card, mainly because the original customer did not admit making a mistake, so I had to make a gapless chain of proof in preparation for a lawsuit. Are you willing to pay for that?

  • I know how hard it is to service and to repair these delicate things and your efforts must be paid well when spending hours.

    I am sure you can work it out and it will be an easy fix now, just I have the feeling.

    I dont understand what do you mean saying "gapless chain of proof in preparation for a lawsuit" but I am willing to pay whatever you want

    because I want to make this card work and enjoy her with my Amiga, if the money will be reasonable. amount of course.

    Just tell me what to do and how much it will cost, pm me in my email.

    Thank you Very Much for answering me, and I promise you to make it as easy as I can for you, and everything will be ok.

    Please help me to make her as new and I will take good care of her! Thank you.

  • The one good thing is that I can be sure now that the customer in question will not start a lawsuit if he's selling off the main evidence.


    Once again, I cannot know if the card is in the same state as I've shipped it to that customer in summer 2017. It will have to be checked again, and I prefer not to give any pricing unless I know what kind of work needs to be done on the card. So just send it - I'll put a "max. 100,- EUR" tag on it to make sure it's not exceeding reasonable limits. Please make sure to include a short note in the parcel, so my employees know what to do with it.

  • If it cost 100 it is not affordable. The shipping costs are at least 40 I think and I can buy a new one plus warranty with 140€.

    Can I send the card , then you check her and tell me a service price?

    If the price is reasonable for me, I will tell you to proceed, else you will send it back to me.

    How much will be the initial test you will make? Also how much the shipping to Greece ?

    Thank you for helping me out it is a difficult case and I regret buying it.

    (* but I think the beast in the card is sleeping and just needs a firmware to wake up *)

  • 1.) remove the DisMo from the card. I don't know if it's still glued or loose, but it needs to go for a test. Just attempt to lift it; it should slide off the pin header in case it's not glued any more. Also remove the pin header - it's better if it's not on the ACA500plus for the basic function test. Just pull on it, there is nothing that keeps it in place but the connector itself.


    2) put the card into de-brick mode; without the DisMo, this can be done with the unpopulated jumper near the 86-pin slot where the mount hole is. It's a three-pin jumper: Make a connection between the center pin and the pin closest to the 86-pin connector.


    3) attach the card to the A500, start it. The computer should come up with 14MHz and a little bit of extra memory. If you have a Kick3.1 chip for the A500, the boot CF slot should also work.


    Please report back what the result of this test is.

  • Sorry for the delay but fortune wasn’t with me.


    First I tried to my spare A500+ motherboard rev8A, KS2.04.37, I tested the mb and it was booting ok without the aca card. Then I put the card without the dismo, also removed the under pins and set the jumpers in de-brick mode. With the aca card it wasn’t booting at all. Maybe one time it booted, I don’t remember, but after a few attempts, a Green Screen occurred! I removed the card and the Green screen remained. After that in my attempts a Dark Red screen like Brown also came. Bad luck. Ram chips beaten. Then I took another exactly the same A500+ r8A, KS2.04.37 and this time it booted Ok. And this mb always was booting.


    In the new A500+ rev8 system started OK, but I couldn’t check that the CPU was running at 14Mhz, how can I check it? But I saw that in RAM added 0.5MB. Wb3.1 reports 459,408 graphics mem and 395,876 other mem. Note that I was using a Gotek usb drive for these tests and a Wb3.1 adf disk.


    Showconfig from wb3.1, reports two types of RAM :

    type $A, attribute $305, Fast and

    type $A, attribute $303 Chip, in addresses $C00000-$C7FFFF and the second at $488-$7FFFF both 0.5 MB.

    In Showconfig, Boards: None.


    Sorry I didn’t manage to find a ks3.1 rom chip but maybe I will make one in the next days and maybe the boot CF will work and I can make additional tests.


    I also tried to boot with UPD500P_installerV11.adf in Gotek but nothing


    Also Amiga is booting with the same behavior AND with the DISMO on the card, showing always 0_ in the de-bric jumpered mode.


    Is there any hope to make this aca work? Thank you very much for your instructions, tell me what else do you want to check.

  • Try Sysinfo or AIBB - both are good to find out the CPU speed.


    I also tried to boot with UPD500P_installerV11.adf

    Why? The Installer will only work if other software assets are installed, especially the scsi.device(s) for the two CF card slots.


    Try the menu update and see if it flashes. You won't see the menu itself work, but if the menu flashes to the latest version booting from the UPD/adf file, there's reason to believe that most of the ACA500plus still works.

  • Finally the CPU reported 14 MHz in sysinfo and not in AIBB. Menu update UPD500p_V0127 is booting and tries to update, finds ACA500+decompressing.. initializing... and I wait and I wait. So I think the heart of the beast is ticking. I tried to play a game Blaze and there were ghost sprites in gameplay. I hope it’s not from ACA. Can I make further tests before I send her to you? New intructions ?

    I'll try and ks3.1 test and then we'll see.

  • The "eternal wait" when flashing might be due to the missing DisMo; if the flash routine attempts to output something, or even set the colour of the LED, it's not going to work and the main logic will wait forever for the DisMo to acknowledge the access.


    My offer would be a new DisMo for this unit, where warranty and right of revocation is limited to the DisMo, and won't extend to the accelerator itself. Please send me an e-mail with your address/shipping details.

  • The last reply was more than 365 days ago, this thread is most likely obsolete. It is recommended to create a new thread instead.