Dragon 32 Ram upgrade issue

classic non-acorn hardware, software & languages
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axeman
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Dragon 32 Ram upgrade issue

Post by axeman » Thu Mar 26, 2020 1:27 pm

I've attempted the standard upgrade detailed here as I have 8 64bit ram chips
http://archive.worldofdragon.org/index. ... 4K_Upgrade

but I'm getting this screen. Anyone got any ideas what might be wrong.

Tried with ic33 pin 8 GND connected and not connected. Seems strange that these instructions ask to disconnect the gnd pin??
IMG_20200326_114304.jpg
IMG_20200326_114406_1.jpg

Prime
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Joined: Mon Jun 01, 2009 12:52 am
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Re: Dragon 32 Ram upgrade issue

Post by Prime » Thu Mar 26, 2020 7:22 pm

axeman wrote:
Thu Mar 26, 2020 1:27 pm
I've attempted the standard upgrade detailed here as I have 8 64bit ram chips
http://archive.worldofdragon.org/index. ... 4K_Upgrade

but I'm getting this screen. Anyone got any ideas what might be wrong.

Tried with ic33 pin 8 GND connected and not connected. Seems strange that these instructions ask to disconnect the gnd pin??
No you need to cut the trace between pin 5 and pin 8, wich will disconnect pin 5 from ground. Pin 8 needs to still be connected to ground, check this by beeping it out to another ground pin on another chip.

Is R73 fitted, should be on the right hand side of the rightmost PIA.

Can you post a picture of the RAM area? Is it one of the boards with half good 64s, or a patchboard or 16x16K?

Cheers.

Phill.

axeman
Posts: 20
Joined: Tue Nov 27, 2018 11:02 am
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Re: Dragon 32 Ram upgrade issue

Post by axeman » Fri Mar 27, 2020 10:35 am

Hi,

Here is a picture of the board

No can't see any R73

Oh and I took all the wiring off to redo it
IMG_20200327_102942.jpg

axeman
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Re: Dragon 32 Ram upgrade issue

Post by axeman » Fri Mar 27, 2020 11:17 pm

Beginning to panic a little as I've replaced with a new ic33 and put back the wiring and still getting the screen shot shown previously. Any ideas?

Prime
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Re: Dragon 32 Ram upgrade issue

Post by Prime » Fri Mar 27, 2020 11:57 pm

Did you cut the tracks as directed in the upgrade guide, if so have you put those back?

Cheers.

Phill.

axeman
Posts: 20
Joined: Tue Nov 27, 2018 11:02 am
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Re: Dragon 32 Ram upgrade issue

Post by axeman » Sat Mar 28, 2020 11:05 am

Yes everything is back as was. Going to check continuity on IC31 IC33 pins

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