48K for Atari 400

[Wrathchild]

A while ago I bought what was advertised on Ebay as a 48K board,

what arrived was just a 16K board in a 48K box (probably the result

of a previous upgrade ), which I only found out after having opened

up the 400 completely to put this in.

 

So the question is - can the board I have (part C014700 Rev F)

be hacked in any way to become a 48K board? (or anything else )

 

I don't see these boards on Ebay (UK) too often, so could try from

the US/elsewhere, or $19.95 from B&C doesn't seem too bad.

 

Looking around I found some interesting old discussion here:

http://www.atari800xl.org/news/?p=1989-04

 

Mark

[+warerat]

A while ago I bought what was advertised on Ebay as a 48K board,

what arrived was just a 16K board in a 48K box (probably the result

of a previous upgrade ), which I only found out after having opened

up the 400 completely to put this in.

 

So the question is - can the board I have (part C014700 Rev F)

be hacked in any way to become a 48K board? (or anything else )

 

I don't see these boards on Ebay (UK) too often, so could try from

the US/elsewhere, or $19.95 from B&C doesn't seem too bad.

 

Looking around I found some interesting old discussion here:

http://www.atari800xl.org/news/?p=1989-04

 

Mark

 

Yes, it could be hacked to be a 48K board, if you modify the power and add decoding logic to use 64Kx1 DRAMs (cutting and wires required!). As a side effect, one could actually have 52K of contiguous RAM (from $0000-$CFFF). A mod like that would essentially give you an 800.

[doctorclu]

Want me to get a few pictures of the pigging back technique that my dad did on my 400?

[Wrathchild]

@both - yes please, the board would be surplus to requirements otherwise, so nothing ventured, nothing gained

[Ansiterm]

I upgraded the 16K board of a 400 to 48K (>15 years ago). It should be in one of the two 400s I still have. It's not for the faint hearted, but if you're handy with a soldering iron, it's doable. I probably still have the step-by-step instructions...but not sure where they are right now. If you want them, I'll rumage around in the storage boxes that contain most of my Atari stuff and see what I can find.

 

@both - yes please, the board would be surplus to requirements otherwise, so nothing ventured, nothing gained

[Almost Rice]

I upgraded the 16K board of a 400 to 48K (>15 years ago). It should be in one of the two 400s I still have. It's not for the faint hearted, but if you're handy with a soldering iron, it's doable. I probably still have the step-by-step instructions...but not sure where they are right now. If you want them, I'll rumage around in the storage boxes that contain most of my Atari stuff and see what I can find.

 

Is this it?

 

If so, I have all the parts laying around.

[Ansiterm]

The instructions I used came from a local Atari users group, but they might have been based on what you linked because that looks very familiar. If you have the figures that go with it, I'd take that as a sign from the Atari gods that I don't have to rummage through my Atari boxes

 

I upgraded the 16K board of a 400 to 48K (>15 years ago). It should be in one of the two 400s I still have. It's not for the faint hearted, but if you're handy with a soldering iron, it's doable. I probably still have the step-by-step instructions...but not sure where they are right now. If you want them, I'll rumage around in the storage boxes that contain most of my Atari stuff and see what I can find.

 

Is this it?

 

If so, I have all the parts laying around.

[Ansiterm]

Ok, I abridged the link and found the figures. I also found my Atari memory upgrade folder. The version I have of the 400 48K upgrade is different, but I'll compare the two when I get home tonight.

 

The instructions I used came from a local Atari users group, but they might have been based on what you linked because that looks very familiar. If you have the figures that go with it, I'd take that as a sign from the Atari gods that I don't have to rummage through my Atari boxes

 

I upgraded the 16K board of a 400 to 48K (>15 years ago). It should be in one of the two 400s I still have. It's not for the faint hearted, but if you're handy with a soldering iron, it's doable. I probably still have the step-by-step instructions...but not sure where they are right now. If you want them, I'll rumage around in the storage boxes that contain most of my Atari stuff and see what I can find.

 

Is this it?

 

If so, I have all the parts laying around.

[awace]

The link is broken and I only have instuction sheet w out diagrams if anyone has info on completing the 16k to 48k mod for a atari 400 please let me know..

I did an original atari 48k mod to a 400 but sold the 400 on ebay so now its off to find a nother 400 to butcher up again at least in will only be inside so noone will see it..

ALso I like the one where you change it to 64k chips I dont care if it only gives 48k though.. I also have 2 32K upgrade boards I recently trashed an 800 cause it was TOAST ugly stained and groose I should have kept the keyboard but

was cleaning.. I did how ever keep the rom and rams chips carts..

I forgot I had had 2 32k rom chips .. IS there a way to mod an atari 400 to use a 32k chip then later swap that to 48k w out having to change any thing??

the 32k chips work instantly in the 800 along w 16k to make 48k I assume if i put both in it would give 64k i guess if i use 2 32k and one 16k would that make 80k??? I dont know weather an unmoded 800 would let me use 80k.

I know I can use a 32k and a 16k .

[+Guitarman]

The link is broken and I only have instuction sheet w out diagrams if anyone has info on completing the 16k to 48k mod for a atari 400 please let me know..

 

The site has been remapped since the original post. Here is the new link to the memory upgrades page

 

 

http://atari.a8maestro.com/info/8ball/ballhc.htm

[awace]

A while ago I bought what was advertised on Ebay as a 48K board,

what arrived was just a 16K board in a 48K box (probably the result

of a previous upgrade ), which I only found out after having opened

up the 400 completely to put this in.

 

So the question is - can the board I have (part C014700 Rev F)

be hacked in any way to become a 48K board? (or anything else )

 

I don't see these boards on Ebay (UK) too often, so could try from

the US/elsewhere, or $19.95 from B&C doesn't seem too bad.

 

Looking around I found some interesting old discussion here:

http://www.atari800x...news/?p=1989-04

 

Mark

 

YOu have to WATCH where you put the rams

the ROM GOES 1st closest to the CART then my has 32K then 16k in the 800

if I put the 16k then the 32K it thinks the 32k is only 16K..

[awace]

the link works now and I have 2 32k ram boards.. I am in the proccess of modding a 16k to 64k if i can understand the links.

then one of the 400's can be modded to 64k.

[ClausB]

The link is broken and I only have instuction sheet w out diagrams if anyone has info on completing the 16k to 48k mod for a atari 400 please let me know..

 

The site has been remapped since the original post. Here is the new link to the memory upgrades page

 

 

http://atari.a8maest...ball/ballhc.htm

 

That link is to a rip-off of the original MACE article which is posted here:

http://www.atariage.com/forums/topic/123207-expanding-the-400/page__view__findpost__p__1488304

[mimo]

I have a couple of the Best Electronics official 48K expansion boards for the 400,

The board has 64K stamped on it, and has 4864 RAM chips in it as standard, can this be moded to give the full 64K?

[Gunstar]

I was going to suggest Best E., glad you did. An educated guess to your 64K question is possibly. The extra 16K is an "under the OS" thing in later Atari's, but your 400/800 OS I think limits it to seeing 48K, also you may need more 4864's than are currently on the board. Maybe if you could mod the 400 with an XL/XE OS it would see all 64k on the board...

 

I'm sure someone can give you a more definitive answer...