I got ripped off on a dead Amiga 4000

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yes played pinball illusions AGA version on it today since that game happens to not detect mouse.  so close so close :|

[wawrzon]

barely any of my a4ks (and i have a few) has the wire from the lock even attached to motherboard. i cant recall mouse not working in such a case.

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that's how this seller is talking too.  like he doesn't know wtf.  also if you read the auction, and he DID have mouse and joystick ports replaced.  They're replacements and they look like they were properly soldered on and attached.  But damn I'm thinking if there's a jumper or a resistor that controls those, there's something messed up with it.  I have to find the info needed to replace mouse & joystick ports and look at it so I can diagnose.  I'm pretty sure that's what we're dealing with since yes, keyboard jumper just disconnected should do it.  Also again let me state I have a good, not tank, Amiga mouse along with the one that came with this 4000 so I know it's not the mouse.  I don't know what it needs.  There is a couple weird jumpers on the A4000.  This one I won't mention because I forgot and it's not the one but this one, CN404 is near the back and by the audio and video outputs and has no jumper on it.  But J975 is right by the mouse and joystick ports and has no connection to it and looking kind of like a place for some sort of power connection but I don't know.  Doesn' look like you're just supposed to stick jumpers there.  CN975 and CN976 are the mouse and joystick ports respectively.  And there isn't anything that looks like a resistor or and jumper spot near them really, besides the PAL/NTSC jumper.  My monitor is a Commodore 1960, so it can handle either just fine and I keep the jumper on NTSC.  I've tried seeing if that effects it anyway but it doesn't as you'd think.  It's just the only jumper close to the mouse so I tried it.  Nothing doing here though.  It's like either more likely mouse port is bad, even though it is this nice replaced one perhaps has come loose (CN975 and maybe CN976 too for joystick), or, this A4000/040 highflyer model happens to have the key hardwired to those in some way other amigas don't.  And you need to maybe solder a resistor in to hack around it or something.  That sounds too crazy to be true but it's anything worth thinking about right now.  It plays and loads games and apps so it's not like I can turn back now!

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*chip only with floppy and only highflyer card, then turn on + 2 mouse buttons held, then turned off and inserted the other daughterboard (zorro one) and boom insert disk screen finally appeared.  turned off,  then proceeded to put the ide HDD back on there and boom, workbench 3.0.  time to grab some 3.1 roms now and a bunch of other stuff for it

the real hardware issue was just that the cpu mainboard wasn't seated properly.  it came off during shipping and it's on weird plastic pegs that are meant to be easy for it to pull off i think because it gets unseated easily.  so to make it totally clear, the real thing that fixed this box was just making sure the cpu card was VERY perfectly seated.  it went out again and i went for the kind of hard to reach cpu card this time.  had to remove the HDD to get at it properly.  you can't seat it right just sticking your fingers in without removing the HDD which is directly behind it. there's not enough room.  still problems.  I really did find this aligator clip that's the right exact size and it turns and clicks perfect into lock and unlock.  and everyone is saying you can disconnect the key.  so it's got to be something wrong somewhere on the motherboard.  it says missing some stuff when workbench starts up but that's nothing to do with this because the mouse doesn't work in games either.

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seller says:

"I’m getting pretty sure there is the problem with the keylock control if the U975 functioning properly as the keylock controls the U205 74HC4066 keyboard control chip and the U131 logic chip and that U131 chip is sending a signal enable or disable to the pin 6 on U975 the that controls the mouse port, only I have to see the schematics and the chip layout to determined the correct action regarding the keylock configuration. As I remember in one position the key is grounding the pin 11 on U131 in other position it release the ground and then there is +5V flow. I’m pretty sure that the CN200 keylock connections middle pin is the ground and the two other ones are +5V so the pin 1 and 3 are the +5V it doesn’t matter if the cable is connected to the pin 1 and 2 or 2 and 3."

and

"If the buttons works on mice that’s means you have the +5V on port and the fuse is ok it is the FB975 (located just behind the port 2) it protects mouse ports the axis control is done by the shift register chip 74HCT166 U975. Try to press done this chip and as you holding at done try to move the mouse check is there any changes."

It sounds like he knows how to fix it but it's too bad if one of those chips is that corroded.  it can happen though.  i do not know anymore right now.  tried pushing down on that U975 chip while booting but that didn't do anything.  any suggestions on what cleaner to use that won't ruin circut boards?  i have this stuff from radio shack that's god awful.  everything you try to clean with it it just gunks up and they call it, electronic cleaner.  but i don't think it's actually safe on any electronics I know of.

[whiteb]

seller says:
 tried pushing down on that U975 chip while booting but that didn't do anything.  any suggestions on what cleaner to use that won't ruin circut boards?  i have this stuff from radio shack that's god awful.  everything you try to clean with it it just gunks up and they call it, electronic cleaner.  but i don't think it's actually safe on any electronics I know of.

The only thing I use on Circuit boards, is pretty much the ONLY thing to use, is Isopropyl Alcohol.  That stuff that evaporates in seconds..

And no, you cannot drink it....

[koaftder]

Have you checked over your stuff with an oscilloscope or at the very least a logic probe?

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I have neither of those tools.  That would be cool if I did.  But all I do know, is contacts in that middle left region of this A4000 motherboard look a bit worn.  All I have is a Volt/Ohm meter that's kind of cheap and I think that's only really for testing power supplies.

Battery was replaced soon enough and right by battery is ok looking.

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I have neither of those tools.  That would be cool if I did.  But all I do know, is contacts in that middle left region of this A4000 motherboard look a bit worn.  All I have is a Volt/Ohm meter that's kind of cheap and I think that's only really for testing power supplies.

Battery was replaced soon enough and right by battery is ok looking.

The U177 chip, whatever that one does, has one of it's feet melted off.  It happens to be the chip right by the battery.  Maybe this guy didn't catch the battery replace in time.  Also the leads on the one I mentioned in the above post looks like crap.  New motherboard rev. B is what I need.  e-mail/pm if you got one.  I got buster chip part #390539-11, which is the later one I think.  So as long as you got the rev. B with the socket for the buster that's what I need.  And one that works of course.

[barney]

On Ebay, sombody is selling two Amiga 4000 motherboard.  One is $79 and the other is $59.

Barney

Disregard this:  the ebay auction says that the memory does not register.

[koaftder]

The U177 chip, whatever that one does, has one of it's feet melted off.  It happens to be the chip right by the battery.  Maybe this guy didn't catch the battery replace in time.  Also the leads on the one I mentioned in the above post looks like crap.  New motherboard rev. B is what I need.  e-mail/pm if you got one.  I got buster chip part #390539-11, which is the later one I think.  So as long as you got the rev. B with the socket for the buster that's what I need.  And one that works of course.

it's a 74HCT174, you should have no problem finding one. Digikey has one for a dollar.

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On Ebay, sombody is selling two Amiga 4000 motherboard.  One is $79 and the other is $59.

Barney

Disregard this:  the ebay auction says that the memory does not register.

totally man I saw those.  They are very shady.  Both of em he ripped the battery out.  I'm going to buy myself some Weller solder gear this afternoon at the computer store because I know if this thing is going to actually get fixed I'm going to have to do it myself the old fashioned way.  I see this guy has a wiring diagram in next post Haven't looked at it yet.  Looking forward to it though.  Too bad.  This guy took care of his motherboard.  But I may not have to worry because he may have another A4000 motherboard he's willing to send me.  I have a feeling he doesn't have a spare but he'll probably take it out of his 4000 and send it.  But I just don't want him to have to.  I mean I'll push him to send one if he has it but I'd be so satisfied if I resolder it myself.  If it's fried chip (this U175 or whatever), then that sucks because I'm pretty sure I'm not going to just find that chip somewhere.  It all adds up to needing a new motherboard unless there's really just a contact issue that needs a little metal to keep it going through.  You gotta be so careful.  This case is cool but what is REALLY cool is that Highflyer Expansion card has a Video Toaster slot in it, and the regular daughterboard, which sits above the Highflyer on this Miggy, only has the 4 Zorro III slots as normal A4000 has.  So whatever happens I have to keep this Highflyer Card and the case because otherwise, you can't fit both daughterboards in there.  We'll keep everyone posted.

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it's a 74HCT174, you should have no problem finding one. Digikey has one for a dollar.

Oh yeah!?  That's what I needed is someone to say what you just said.  I'm not a PCB expert I just can do this type of work when I have to.  So it's sort of a common chip I guess then.  I thought it was something like the Lisa or Super Buster where it's an Amiga exclusive.  This advice is VERY helpful for what I'm attempting this afternoon.  Thank you!

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FC74HCT166T is the identifier on the chip below that it says 323820D and KS59310PBY

I don't nee that other one I guess because that just controls the RTC.  I also need a new IDE connector to solder to the motherboard.  Looking for both these things at the site.  Cannot find the FC74HCT166T chip.

[T3000]

Incase (no pun intended) there are some folks that have yet to see this behemoth. Here is an ad out of Video Toaster User. Febuary 96



AmigaDave has one of these units. (saw it at AmiWest 2008)

[koaftder]

FC74HCT166T is the identifier on the chip below that it says 323820D and KS59310PBY

I don't nee that other one I guess because that just controls the RTC.  I also need a new IDE connector to solder to the motherboard.  Looking for both these things at the site.  Cannot find the FC74HCT166T chip.

Is it a DIP chip? See this:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=296-2099-5-ND

For the IDE connector, see this: (could somebody double check that to make sure it's the right one?)
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=MHB40K-ND