Mods to My A1200 1d4 Mobo. What are they ??

cosmicfrog · 06 March 2011, 09:33

Well just spent all night takeing my Ez Tower apart, Started off as a rebuild but my GVP HC+8 scsi card wouldt play nicely so I decided to investigate

The culprit A1200 1d4 Motherboard

On taking the motherboard out to see if the timing fixes have been done I discovered someone had been there before me and done timing fixes plus they have done some other stuff as well. Now I don`t like the looks of E127R but I cant get a good picture of it to show. Any way on with the pics

Back of the 1d4 A1200 Mobo

Timing fixes
E123C, E123R, E125C, E125R are clearly missing Missing But E127R looks like its been buried in solder

I have no Idea what this dose or is for but I`m guessing it has something to do with the PCMICA port

Is this the wire mod from an Escom Amiga Technologies A1200

So not only a dose of P0rn but a Q&A session to, Plz help. I want to know what these things are so I can put it all back in the tower, Thanks and ribbits

fitzsteve · 06 March 2011, 10:18

Thats looks the same as my 1d4 board which has the eyetech fixes applied.

I can't find details of exactly what online, hopefully someone else can fill us in.

Interesting experiment would be to try an ACA1230 on these boards!

Steve.

cosmicfrog · 06 March 2011, 11:18

sorta makes sense as all the stuff in the tower was from Eyetech, Ez this, Ez that, Ez Bloody Ribbits

well according to SPS the wire is to undo the escom floppy mod

just want to know what all that other stuff on the black tape is about now

rockape · 06 March 2011, 13:54

Hi,

See http://www.ianstedman.co.uk/Amiga/am..._mobo_fix.html

I hope this helps.

Regards, Michael

aka rockape

Editted out uneccessary pics

cosmicfrog · 06 March 2011, 14:06

Nope it dos`t and why you quote all those pics ???
but thanks any way

Mick · 06 March 2011, 15:41

The last one is defintely floppy ready signal fix for support of Commodore compatible drives (I did it myself on mine).

It seems like in the middle one the PCMCIA is connected to the IDE connector in some way? could it be so that the hard disk LED lights up with PCMCIA activity or something like that? (purely guesswork)

FOL · 06 March 2011, 16:30

Last but one is the PCMCIA reset fix.

cosmicfrog · 06 March 2011, 17:39

Kewl Thanks FOL

first time I have seen these fix`s in the flesh
nice to know then Mobo is fixed, shame I probably wont use the pcmcia port but its good to know its sorted

Thanks and Ribbits ppl

rkauer · 06 March 2011, 22:53

Just the accelerator timing fix is wrong: you must sack out E123R & E125R OR E123C & E125C, not sack out all four pieces.

Replace the capacitors or the resistors, else you'll get "funny" behaviour with one accelerator attached.

--

The shorted E127R is the "cure" for video artefacts when using high AGA screen modes.

The funky transistor+resistors is the best known PCMCIA fix.

Mick · 07 March 2011, 01:33

Quote:

Originally Posted by rkauer

you must sack out E123R & E125R OR E123C & E125C, not sack out all four pieces.

Is one choice better than the other or does it make no difference?

FOL · 07 March 2011, 02:09

Quote:

Originally Posted by rkauer

The shorted E127R is the "cure" for video artefacts when using high AGA screen modes.

Ah, didnt know that.
So this solves Amiga Tech boards high resolution issue after it warms up?

Quote:

Originally Posted by rkauer

Just the accelerator timing fix is wrong: you must sack out E123R & E125R OR E123C & E125C, not sack out all four pieces.

Replace the capacitors or the resistors, else you'll get "funny" behaviour with one accelerator attached.

Really?
The caps go to ground, but the resisters go to Alice.
I have seen loads of boards with all 4 removed.

rkauer · 07 March 2011, 02:45

Ian's site points to only removing the resistors, but you can choose to sack the capacitors, but as far as I know, not all of them.

About the E127R (which is a ferrite bead on later boards and a resistor on earlier ones), yes, that's the cure for artefacts on high screen modes, even on earlier boards.

I had to do this my (now defunct) 1D1 because the screen glitches.

FOL · 07 March 2011, 12:08

Quote:

Originally Posted by rkauer

Ian's site points to only removing the resistors, but you can choose to sack the capacitors, but as far as I know, not all of them.

About the E127R (which is a ferrite bead on later boards and a resistor on earlier ones), yes, that's the cure for artefacts on high screen modes, even on earlier boards.

I had to do this my (now defunct) 1D1 because the screen glitches.

Now thats interesting, will have to do some testing.
Thanks for the info.

Eclipse · 07 March 2011, 23:39

Is it this one?

mfilos · 08 March 2011, 00:21

Wow. I never seen this diagram nor I knew about a PCMCIA reset fix with Resistors and Transistor!!!
I only knew about a 10μF capacitor between CC_RESET and Vcc.

FOL · 08 March 2011, 09:10

Quote:

Originally Posted by mfilos

Wow. I never seen this diagram nor I knew about a PCMCIA reset fix with Resistors and Transistor!!!
I only knew about a 10μF capacitor between CC_RESET and Vcc.

We sell a board called the PCMCIA Reset Adapter, which clips onto the Gayle chip.

mfilos · 08 March 2011, 10:26

I know that FOL. Is this Gayle Adapter using the transistors+Resistors as well (instead of the normal Capacitor mod)?
Also, is it compatible with A600's Gayle?

FOL · 08 March 2011, 13:42

Quote:

Originally Posted by mfilos

I know that FOL. Is this Gayle Adapter using the transistors+Resistors as well (instead of the normal Capacitor mod)?
Also, is it compatible with A600's Gayle?

Yes, it uses resistors and transistor.

Never tried it on the A600 as it doesnt suffer from the reset problem.

mfilos · 08 March 2011, 13:51

Quote:

Originally Posted by FOL

Yes, it uses resistors and transistor.

Never tried it on the A600 as it doesnt suffer from the reset problem.

Don't be so sure of that.

I had this issue on 2x A600 mobos (on a previous 2D revision and now on an 1.5).
- Without CardReset & CardPatch the A600 freezes when Genesis (of 3.9) gets online.
- With CardReset & CardPatch the A600 works just fine without freezes!!! Go figure.

Since I wanted to get over with this issue once and for all (and without software hacks) I thought of doing the capacitor mod sometime in the following days until I saw the one with Transistor & Resistors.
I think I'll order one ready from AmigaKit just to test it out.

AFAIK Gayle pin assignment is the same in A600 and A1200 isn't? (Iirc Rkauer told that in a previous post of mine regarding that matter).

rkauer · 09 March 2011, 06:47

Yes, both parts are exactly the same.

06 March 2011, 09:33	#1
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 56 Posts: 3,557	Mods to My A1200 1d4 Mobo. What are they ?? Well just spent all night takeing my Ez Tower apart, Started off as a rebuild but my GVP HC+8 scsi card wouldt play nicely so I decided to investigate The culprit A1200 1d4 Motherboard On taking the motherboard out to see if the timing fixes have been done I discovered someone had been there before me and done timing fixes plus they have done some other stuff as well. Now I don`t like the looks of E127R but I cant get a good picture of it to show. Any way on with the pics Back of the 1d4 A1200 Mobo Timing fixes E123C, E123R, E125C, E125R are clearly missing Missing But E127R looks like its been buried in solder I have no Idea what this dose or is for but I`m guessing it has something to do with the PCMICA port Is this the wire mod from an Escom Amiga Technologies A1200 So not only a dose of P0rn but a Q&A session to, Plz help. I want to know what these things are so I can put it all back in the tower, Thanks and ribbits

06 March 2011, 11:18	#3
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 56 Posts: 3,557	sorta makes sense as all the stuff in the tower was from Eyetech, Ez this, Ez that, Ez Bloody Ribbits well according to SPS the wire is to undo the escom floppy mod just want to know what all that other stuff on the black tape is about now Last edited by cosmicfrog; 06 March 2011 at 11:58.

06 March 2011, 13:54	#4
rockape Registered User Join Date: Feb 2010 Location: Lincolnshire, England. Age: 75 Posts: 167	"Ian Steadmans helpfull site for motherboard Modifications" Hi, See http://www.ianstedman.co.uk/Amiga/am..._mobo_fix.html I hope this helps. Regards, Michael aka rockape Editted out uneccessary pics Last edited by rockape; 06 March 2011 at 14:50.

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06 March 2011, 10:18	#2
fitzsteve Professional slacker! Join Date: Jul 2009 Location: Kent, UK Age: 44 Posts: 6,685	Thats looks the same as my 1d4 board which has the eyetech fixes applied. I can't find details of exactly what online, hopefully someone else can fill us in. Interesting experiment would be to try an ACA1230 on these boards! Steve.

06 March 2011, 14:06	#5
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 56 Posts: 3,557	Nope it dos`t and why you quote all those pics ??? but thanks any way

06 March 2011, 15:41	#6
Mick Registered User Join Date: Jan 2004 Location: Yorkshire Posts: 735	The last one is defintely floppy ready signal fix for support of Commodore compatible drives (I did it myself on mine). It seems like in the middle one the PCMCIA is connected to the IDE connector in some way? could it be so that the hard disk LED lights up with PCMCIA activity or something like that? (purely guesswork)

06 March 2011, 16:30	#7
FOL PSPUAE DEV Join Date: Nov 2006 Location: Wales / UK Age: 45 Posts: 6,047	Last but one is the PCMCIA reset fix.

06 March 2011, 17:39	#8
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 56 Posts: 3,557	Kewl Thanks FOL first time I have seen these fix`s in the flesh nice to know then Mobo is fixed, shame I probably wont use the pcmcia port but its good to know its sorted Thanks and Ribbits ppl

06 March 2011, 22:53	#9
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 58 Posts: 3,482	Just the accelerator timing fix is wrong: you must sack out E123R & E125R OR E123C & E125C, not sack out all four pieces. Replace the capacitors or the resistors, else you'll get "funny" behaviour with one accelerator attached. -- The shorted E127R is the "cure" for video artefacts when using high AGA screen modes. The funky transistor+resistors is the best known PCMCIA fix.

07 March 2011, 02:45	#12
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 58 Posts: 3,482	Ian's site points to only removing the resistors, but you can choose to sack the capacitors, but as far as I know, not all of them. About the E127R (which is a ferrite bead on later boards and a resistor on earlier ones), yes, that's the cure for artefacts on high screen modes, even on earlier boards. I had to do this my (now defunct) 1D1 because the screen glitches.

07 March 2011, 23:39	#14
Eclipse Turpentine Join Date: Oct 2007 Location: Kent, United Kingdom Posts: 744	Is it this one?

08 March 2011, 00:21	#15
mfilos Paranoid Amigoid Join Date: Mar 2008 Location: Athens/Greece Age: 45 Posts: 1,978	Wow. I never seen this diagram nor I knew about a PCMCIA reset fix with Resistors and Transistor!!! I only knew about a 10μF capacitor between CC_RESET and Vcc.

08 March 2011, 10:26	#17
mfilos Paranoid Amigoid Join Date: Mar 2008 Location: Athens/Greece Age: 45 Posts: 1,978	I know that FOL. Is this Gayle Adapter using the transistors+Resistors as well (instead of the normal Capacitor mod)? Also, is it compatible with A600's Gayle?

09 March 2011, 06:47	#20
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 58 Posts: 3,482	Yes, both parts are exactly the same.

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