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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: mradam83 on December 27, 2014, 03:56:42 PM
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Hi Amigans, first of all I hope you've all had a good Christmas.
I'm having a big problem with my A1200.
I have one with the standard 3.0 rom chips and no other modifications to it - it still works on an internal floppy, no hard drive, no accelerators, and save for a minor issue with saving games which I sorted it has been fine for the past few weeks of having it.
For Christmas, I was gave some 3.1 rom chips (it is a 1200 set, not for the 500 or 600 Hyperion entertainment) a new keyboard and a cf hard drive kit along with a new set of 3.1 workbench discs.
So I followed the instructions to a tee that I've found on here and that came with the new components - careful removal with a flat edge screw driver until the original 3.0 chips were out followed by placing the new chips in carefully with the first socket empty. I've also put the new cf drive kit in and replaced the keyboard before reassembling the Amiga.
I turned the Amiga on and got nothing on screen. The power light is on the machine and the floppy light is on all the time static - when there's no disc in the drive, it doesn't make the usual clicking noises that an empty drive makes and if you put any discs in it doesn't start to read them.
I took the cf hard drive kit out and tried the Amiga again but the same happened. I've tried just taking the chips out and putting them back in but nothing still.
I've tried to put my original 3.0 chips back in and after I did, the same happened - nothing on screen, no drive clicking noises and static lights on the power and floppy led.
So as you can imagine I'm very gutted/worried. Has anyone ever came across this before? All the new components are from http://www.amigakit.com as far as I'm aware and previously I've only played games on it such as Frontier Elite which have been working fine.
Is it screwed?
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I hate to ask the obvious question but did you insert the rom chips the right direction?
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I did indeed - I made sure the dimples (for want of a better word) were installed the right way as per the instructions ie matching up to the same shape on the motherboard.
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Hmmm...
Perhaps when you connected the IDE cable to either the Amiga or the CF interface the cable pins weren't lined up correctly? I've done this myself a couple of times before where I had only connected half of the IDE cable up... luckily no damage was caused in my instances.
Also, when you inserted the new rom chips the first time are you sure you had them in the right-most holes in the rom sockets?
Worthwhile checking voltages too if you have a multimeter. There should be 5V, 12V and -12Vdc. On the floppy connector check for 5V and 12V.
Also, check that the floppy cable is connected correctly both ends too...as the floppy light being lit but no noise sounds a lot like a dodgy floppy connection. I've done that before too...
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Disconnect everything and just have the motherboard and PSU, turn it on and see what you get.
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sounds like the roms might be swapped in their sockets. swap them and see if that helps. keep the polatiry with the notch/dot correct tho!.
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I'm a bit worried in case the first time I put the chips either in the wrong sockets (as in u6a in u6b and u6b in u6a) or in the first hole the first time I installed them. I cant remember if I did but if so, would it permanently mess the motherboard up?
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Also, I have noticed a peculiar thing.
If I use the soft reboot (A, A and Ctrl) I notice the main power light dims as if it resets and then goes back to normal once released. I'm still having the same issues as regarding no picture, and sometimes I hear one solitary click from the disc drive the first time it's turned on but that's it.
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You really need to disconnect the floppy drive like someone above has instructed. Until you test the bare motherboard you'll find it hard to diagnose. Sounds exactly like the floppy drive cable has been connected upside down by the symptoms you describe.
Test with only power and video output connected. Absolutely no other expansions or peripherals.
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Eureka!
You lot are all very fine people - I've done what you all said, and it now works! It was a combo of my floppy being in wrong and the modulator being really old and falling out all of the time.
Thank you so much everybody!
I'm surprised the 3.1 roms has no insert disc screen like the 3.0 kickrom does, is that because the chip is a later one not made by Commodore after Amiga changed hands? It all works fine by loading discs etc and the hard drive works so I have no reason to think it's a problem with the chip as such.
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I'm surprised the 3.1 roms has no insert disc screen like the 3.0 kickrom does, is that because the chip is a later one not made by Commodore after Amiga changed hands? It all works fine by loading discs etc and the hard drive works so I have no reason to think it's a problem with the chip as such.
The 3.1 does have an insert disk screen, it takes awhile for it to appear sometimes due to the looking for HDD delay.
Although you wont see this screen when you have a HDD installed.
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And that dimmed led is standard when holding down Ctrl-A-A'