Boot problems on modded a4000

[tormedhammaren]

@Framiga:

This is beginning to be a thread with lots of specs and info making it easy to misunderstand. :-) The problem is that I can't see any video output (I've pulled out the Spectrum). And I am just trying to get normal PAL display from the "RGB port" but there is just a black screen. There is no hd in the machine at the moment.

Regards,
Tor

[Framiga]

@ tormedhammaren

check anyway your boot disk (it should been modded from the previous owner).

Check in the floppy Devs:Monitor, wich driver is present. (if it empty, should boot anyway from the kickstart PAL monitor).

If those floppy was modded, probably the Screenmode preference, should be wrong too.

Not an easy situation :-(

Ciao

[tormedhammaren]

@Framiga:
Not even the purple screen with the workbench disk beeing inserted is shown. So i supose there is a malfunction in the hardware. But the machine is working (the OS loads).

Not an easy situation :-(

Luckily I haven't paid yet, and wont do it either if I can't fix the machine.

Regards,
Tor

[Amiga4k]

As harsh as this sounds, pull every card. Lets get back to the basic motherboard with a floppy drive.
Does that work? Then add to it. Your pounding to death a theory without really knowing if the motherboard is really at fault, or the Warp card.
Also, take the monitor off the video card for now. That will by-pass the card (for now).

[Cass]

What happens is that when I switch on my machine the power LED brightens up after about half a second, the CAPS
lock light works the way it should (no freeze after 10 events) and the floppy starts to tick after some time. If I then insert the
Workbench disk, Workbench loads from the disk. This means that the CPU card and the ROM are working.

Nice, it's perfectly working!

But - the machine still gives out just a black screen. I've got a video --> scart cable connected to the "RGB port". I've
tested the cable with another machine - so I am certain that it works.

Could have been the monitor definitions (devs:monitors/) to redirect the video-out to the card, but since you don't see any "early-startup-menu", that means you have an RGB out problem.

- Check the pins on the RGB-out plug (AMiGA)

- Check the plug on the mobo side, and the first electronic components between LISA and RGB-out plug (resistors, capacitors, motherboard traces).

If here was a custom chip fault, you could not boot and the CapsLock is blocked with no floppy ticks.
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IPAD GUIDES

[tormedhammaren]

@Amiga4k:
I have allready pulled out every card. Just sitting on the basic mother board with a floppy drive. I have stated this before :-)

@Cass:

Could have been the monitor definitions (devs:monitors/) to redirect the video-out to the card, but since you don't see any "early-startup-menu", that means you have an RGB out problem.

- Check the pins on the RGB-out plug (AMiGA)

- Check the plug on the mobo side, and the first electronic components between LISA and RGB-out plug (resistors, capacitors, motherboard traces).

If here was a custom chip fault, you could not boot and the CapsLock is blocked with no floppy ticks.

I will check these things. Can I test resistors, motherboard traces and capacitors with a multimeter?

Regards,
Tor

[patrik]

@tormedhammaren:

Are you 100% sure that the TV in question can handle a RGB-signal?


/Patrik

[Cass]

Can I test resistors, motherboard traces and capacitors with a multimeter?

Well, a simple inspection firstly will do (note any strangely-blacked component, disrupted traces etc.)

As for the tester, any electronic component should be tested by itself not in a circuity. That means much work, done by a specialist....

A simple thing to do is to test only suspected faulty:

- resistors (should give infinite resistance if burnt), if inplace may give any value (altered by the circuity).

- capacitors (should give an infinite value in case they're faulty), if normal they peak a 0 Ohm resistance that increases to infinite in short time.

- mobo traces should give 0 Ohm values if tested between 2 direct points (not any resistor/capacitor/IC between the tester leads).


Check the RGB-out plug and its pins to the mobo first, and then move proximaly to the mobo components


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ASIAN PETITE