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Hi,

I have a D32 which just displays a blank green screen. I've checked the +-5, 12 voltages which are all ok on the ram ,cpu, sam and various other places so I think the voltages are ok.

I've also swapped all the socketed chips into a working dragon and they all work ok.

Anyone got any ideas or troubleshooting tips?

Please excuse the colour on my TV as its been in a war with the ground and didn't fair to well.

Thanks in advance

If you also swapped the rom chips, it may be that some ram chips are faulty.

This little YouTube video might come handy if you're into checking the memory.

Latest update to this issue is that I ended up not socketing and replacing the Ram as I thought I would first try socketing the right most ROM chip as some have said it is a major cause of such symptoms but that didn't help and the ROM was fine. I did however have a major breakthrough with getting this to work as when I touched the 14.218Mhz crystal (x2) I got a cursor to appear sometimes and then by gently pressing the crystal between finger and thumb I could get the machine to boot!!

It is very hit and miss (bit like holding up an antenna while standing on one leg sort of thing) but it is a big clue.

I've tried swapping the crystal but still the same so I'm going to do some testing of components connected to and around the crystal

Turns out touching the crystal to get it to boot wasn't a clue but it did allow me to test the keyboard.

I could only get key h,x,8,0 to work so this was a big clue. Traced the fault to the PIA 6821 IC26. Removed it and socketed then tested in a working machine and got the same fault, no boot up and blank green screen.

Replaced with a good pia and finally it works !!!!!

Thanks guys for all your help.

Another Dragon Lives....

Great stuff!