GD Rom set up not working 100%

PCB problems and fixes
Post Reply
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

GD Rom set up not working 100%

Post by Red5 »

I have a GDrom, Net Dim, Naomi 1 mob all the cables:
mob proven to work, when power'd up with net dim in, i get nothing on screen, switch off, insert disk and switch back on, Disk can be heard booting etc, black / dark grey screen on crt,
then nothing, couple mins later the drive makes a typical DC drive noise, but still no picture / sound.

have two disk, and two dongles, have been told the GD rom can take a good few mins to load, so have left for 10+ mins at a time, still no joy :problem: :think:

D
Image
User avatar
The Enigmatic Form
Posts: 395
Joined: August 20th, 2008, 5:31 pm
Location: Hannover, Germany

Re: GD Rom set up not working 100%

Post by The Enigmatic Form »

No matter what, there should always be something on screen if the mobo works, even when the GD loads. Do you have another motherboard, or can you 100% confirm that it works with carts?
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

The Enigmatic Form wrote:No matter what, there should always be something on screen if the mobo works, even when the GD loads. Do you have another motherboard, or can you 100% confirm that it works with carts?
Sorry should of said, i have 2 fully working namoi 1 Mobs, work 100% with carts, boot screen etc without carts in.
one has a BIOS that the last owner said worked with NET booting :problem:
Image
User avatar
KmanSweden
KmanSweden
Posts: 1282
Joined: October 13th, 2010, 10:37 am
Location: Stockholm, Sweden
eBay: KmanSweden
Initials: PKK
Contact:

Re: GD Rom set up not working 100%

Post by KmanSweden »

Red5 wrote:
The Enigmatic Form wrote:No matter what, there should always be something on screen if the mobo works, even when the GD loads. Do you have another motherboard, or can you 100% confirm that it works with carts?
Sorry should of said, i have 2 fully working namoi 1 Mobs, work 100% with carts, boot screen etc without carts in.
one has a BIOS that the last owner said worked with NET booting :problem:
You need to change 3 jumper inside the Dimm to switch between Netboot and GD-Rom.
Up the Irons!
User avatar
Chi
Fire Extinguisher
Posts: 904
Joined: August 18th, 2008, 12:55 am
Location: Croydon, UK
Initials: CHI

Re: GD Rom set up not working 100%

Post by Chi »

You've got the second power connector attached (the 6-pin one)?
"TO THE untrained eye Christian Cooper might have been stamping out a small fire " - The Times, 7th Feb, 2004
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

GD rom has all the cables connected and i can hear and feel it working, i just get nothing on the screen , no naomi splash screen, no errors zip

Even though i can not see any error codes, i have read that the daughter board on the dim board can become unseated, so i have opened and reseated, set the jumpers and still nothing. :think: power down and put a game cart in and instant working game :twisted:
Image
User avatar
thomj
Just a few screws loose
Posts: 1738
Joined: June 13th, 2010, 12:05 am
Location: East Yorkshire
Initials: TWJ

Re: GD Rom set up not working 100%

Post by thomj »

have you metered it?

made sure the dimm is properly seated?
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

thomj wrote:have you metered it?

made sure the dimm is properly seated?
not attempted metering yet, but de cased both the mob and the Dimm , so relative certain that there seated snuggly :think:
Image
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

thomj wrote:have you metered it?

made sure the dimm is properly seated?
Voltages tested 5.2 with a load :think:
Image
User avatar
wonderbanana
You can't polish a turd, but I can
Posts: 939
Joined: January 16th, 2011, 2:57 pm
Location: Herts, UK

Re: GD Rom set up not working 100%

Post by wonderbanana »

Red5 wrote:
thomj wrote:have you metered it?

made sure the dimm is properly seated?
Voltages tested 5.2 with a load :think:
Someone may correct me but I was always advised here that's too high for Naomi.

Should be 5.0 to 5.1 ish.
markedkiller78 wrote:that's probably my best contribution to the forum to date "I am pluralising fanny"
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

wonderbanana wrote:
Red5 wrote:
thomj wrote:have you metered it?

made sure the dimm is properly seated?
Voltages tested 5.2 with a load :think:
Someone may correct me but I was always advised here that's too high for Naomi.

Should be 5.0 to 5.1 ish.
Well its bang on 5.00 now, still no joy, could the higher voltage have damaged the Dim board? .2 over the recommended does not seem excessive :problem: :think:
Image
User avatar
kernow
:problem: child
Posts: 14955
Joined: August 17th, 2008, 2:01 pm
Location: Devon
Initials: KRN
Contact:

Re: GD Rom set up not working 100%

Post by kernow »

I also remember reading the naomi is very, very susceptable to a slightly high +5 and is easy to fry compared to other boards

or something.

_o_
David... The wind blows... The wind blows... Bits of your... life awayee
User avatar
wonderbanana
You can't polish a turd, but I can
Posts: 939
Joined: January 16th, 2011, 2:57 pm
Location: Herts, UK

Re: GD Rom set up not working 100%

Post by wonderbanana »

Red5 wrote:
Well its bang on 5.00 now, still no joy, could the higher voltage have damaged the Dim board? .2 over the recommended does not seem excessive :problem: :think:
I know for certain that game carts can have the buffer chips fried at 5.2, I would assume net dimms are similar in that respect? :think:

Cageman & Andy iirc seemed to know most about this sort of thing though, I'm only repeating what I've been told tbf.
markedkiller78 wrote:that's probably my best contribution to the forum to date "I am pluralising fanny"
purplec
Posts: 600
Joined: August 17th, 2008, 6:51 pm
Location: Dublin, Ireland

Re: GD Rom set up not working 100%

Post by purplec »

what you do to get it working, share the wealth :lol:
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

purplec wrote:what you do to get it working, share the wealth :lol:
What? :wtf:
Image
purplec
Posts: 600
Joined: August 17th, 2008, 6:51 pm
Location: Dublin, Ireland

Re: GD Rom set up not working 100%

Post by purplec »

Red5 wrote:
purplec wrote:what you do to get it working, share the wealth :lol:
What? :wtf:
Sorry im extremely tired and for some reason I read "now working" when it actually say "not working" sorry il either go have a cookie or go to bed.
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

purplec wrote:
Red5 wrote:
purplec wrote:what you do to get it working, share the wealth :lol:
What? :wtf:
Sorry im extremely tired and for some reason I read "now working" when it actually say "not working" sorry il either go have a cookie or go to bed.
lol ;)
Image
User avatar
Red5
Posts: 521
Joined: August 14th, 2009, 6:31 pm
Location: Congleton, Cheshire
eBay: dazpaulhill
Initials: DAZ

Re: GD Rom set up not working 100%

Post by Red5 »

another day, another Dimm now works 100%, re-checked the 5volt and 3 before inserting, 5.00v and 3.25, could not get the 3 volt any lower :think:

odd if .2 over the norm has fried the Dimm, as i would say there would of been more variation that that from cabs coming out of the factory, but who knows.
Image
User avatar
grantspain
Tech Head
Posts: 4576
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: GD Rom set up not working 100%

Post by grantspain »

its 3.3 volts anyway
User avatar
wonderbanana
You can't polish a turd, but I can
Posts: 939
Joined: January 16th, 2011, 2:57 pm
Location: Herts, UK

Re: GD Rom set up not working 100%

Post by wonderbanana »

Red5 wrote:could not get the 3 volt any lower :think:
I didn't realise you needed this lower than 3.3??? Has anyone advised different matey???
markedkiller78 wrote:that's probably my best contribution to the forum to date "I am pluralising fanny"
Post Reply