RAM 320XL

[+Nezgar]

Also theres potentially a future external U1MB

 

 

[davince]

Thanks all for the suggestions! I'm going to look into them My goal is to run all those newly demos for Atari (some require 320KB if i'm not mistaken). I do have a SDrive-MAX project ready to try out when I finish the SIO connector.

So would both options (syscheck or turbo freezer) be valid for running those demos of a SDrive-MAX?

Syscheck is available from Germany...my neighbor So think that is the easiest way. Syscheck ram upgrade uses (only?) RAMBo scheme? Will this be a problem running all available demos?

 

Edited March 15, 2021 by davince

[+MrFish]

Turbo-Freezer 2011 uses Rambo. It should be fine for most demos.

 

As far as SDrive-Max goes, I've never heard of any incompatibilities with Turbo-Freezer 2011.

 

One thing to note about the Syscheck, is that it comes with no enclosure. The Turbo-Freezer 2011 (as you can see through the link I posted) has a small connector PCB (for PBI or ECI) and the device cased in a standard AtariMax translucent cartridge shell. The Turbo-Freezer's also more compact in size -- or at least doesn't stick out from the back of the computer as far (using ECI)...

 

Edited March 15, 2021 by MrFish

[BillC]

18 hours ago, MrFish said:

One thing to note about the Syscheck, is that it comes with no enclosure.

Enclosures are in development.

 

[thomas3120]

I apologize in advance for this question..

I have the RamboXL 256k installed in my Atari 800xl.  I remember swapping out the 8 64k drams for 256k drams.

Can this be done to get 320k?  (using 320k drams x8)

 

t

Edited December 24, 2021 by thomas3120

[_The Doctor__]

22 minutes ago, thomas3120 said:

I apologize in advance for this question..

I have the RamboXL 256k installed in my Atari 800xl.  I remember swapping out the 8 64k drams for 256k drams.

Can this be done to get 320k?  (using 320k drams x8)

 

t

If you had the old 64 k chips you could make a 320k memory upgrade combining them and adding support chips for it.... last I knew there aren't any 320k spec chips...

you might go for 128k chips of 256 k chips and make 384k or 512k respectively... though when crossing to 512k you lose internal basic...

Edited December 24, 2021 by _The Doctor__

[thomas3120]

15 minutes ago, _The Doctor__ said:

If you had the old 64 k chips you could make a 320k memory upgrade combining them and adding support chips for it.... last I knew there aren't any 320k spec chips...

you might go for 128k chips of 256 k chips and make 384k or 512k respectively... though when crossing to 512k you lose internal basic...

yes i have some of the original 64k ones but you lost me after that...

So do all the 256k ram ics stay (x8), do you replace soe of those with 64k?

I noticed before all ram was socketed, all but the 3 closest to the user (upper U's i believe)

 

Also, I wouldn't be changing anything to the RamboXL pcb would I?

t

Edited December 24, 2021 by thomas3120

[_The Doctor__]

no, it does not work that way... you would have the base 64k plus an add on board. for your 256k chips and the supporting circuitry

it's simple math... 64 plus 256=320k

256 and 256 is 512

in all cases you need support for the extra memory... you can't just plop whatever you want in the original ram sockets...

 

this really should be it's own thread....

 

but to be relevant, it might be easier or cheaper to just get pre made memory upgrades, internal or external and have them installed for you etc.

Edited December 24, 2021 by _The Doctor__

[ClausB]

To add 64K back in you would piggy back them onto the 256K chips, a messy mod at best. Also the RAMbo board won't support that, so you would need more logic chips for even more mess.

Edited December 24, 2021 by ClausB

[oracle_jedi]

3 hours ago, ClausB said:

To add 64K back in you would piggy back them onto the 256K chips, a messy mod at best. Also the RAMbo board won't support that, so you would need more logic chips for even more mess.

 

And even if you were willing to go to that much trouble, you'd be better off using 8 more 256K chips and getting 512K total.   For the few $$$ you'd save recycling the 64K chips it wouldn't be worth it IMHO.

 

Atarimax used to sell a 512K upgrade board based on Claus' design, which is also the template for the Rambo.

[olliraa]

Is this (or some other external RAM upgrade for 800XL) currently available somewhere?

[davince]

https://www.sellmyretro.com/offer/details/512-ram-expansion%2C-atari-800-xl-61296 is maybe an option?

28 minutes ago, olliraa said:

Is this (or some other external RAM upgrade for 800XL) currently available somewhere?

 

[olliraa]

3 hours ago, davince said:

https://www.sellmyretro.com/offer/details/512-ram-expansion%2C-atari-800-xl-61296 is maybe an option?

 

Awesome, ordered!  Thank you for the tip!

[Beeblebrox]

3 hours ago, davince said:

https://www.sellmyretro.com/offer/details/512-ram-expansion%2C-atari-800-xl-61296 is maybe an option?

 

@davince Just a quick question. I see this particular 512K PBI expansion is powered by the 5v on the port 2 joystick port, (pin 7 I believe carries the 5V line).

 

Presumably if your 800XL already happens to have the PBI 5v power mod/patch line wired up internally, (illustrated here for example), and therefore expansion is then powered via the PBI directly - you would need to ensure the joystick power was not connected as well to avoid frying it?

 

At present this particular Ram expansion mod takes up said joystick port. Fine if you only use the one joystick, but if you have a second or other devices, (mice/Trakball) it's a consideration. 

[+Larry]

This question has popped up several times.  My understanding is that NO, so long as the +5v is coming from the same source, there is no issue.  Perhaps a more tech-savvy individual can explain WHY.  And perhaps also explain what happens when the +5v connection is from two different sources.

[Beeblebrox]

11 minutes ago, Larry said:

This question has popped up several times.  My understanding is that NO, so long as the +5v is coming from the same source, there is no issue.  Perhaps a more tech-savvy individual can explain WHY.  And perhaps also explain what happens when the +5v connection is from two different sources.

@Larry  that would make sense being ok if coming from the same 5V line source I guess. I am assuming 2 x separate internal 5V sources would be an issue 

[Peri Noid]

On 5/1/2010 at 7:02 PM, ctirad said:

Also, an unexpanded 16kB 600XLs can be upgraded to 320XL without any additional work.

I know, it's a kind of archeology, but it happend so that I bought a 320XL expansion. And it works fine with an 800XL and an expanded 600XL. But yesterday I found this thread and I read the first post. And the quoted sentence caught my attention. I have an unexpanded 600XL board. I gave it a try with 320XL - but no, it doesn't want to start. The board works fine with 1064. Is there something else that needs to be done or the above statement isn't true?

Edited Wednesday at 07:24 PM by Peri Noid

[TGB1718]

1 hour ago, Larry said:

This question has popped up several times.  My understanding is that NO, so long as the +5v is coming from the same source, there is no issue.  Perhaps a more tech-savvy individual can explain WHY.  And perhaps also explain what happens when the +5v connection is from two different sources.

If the 5V is sourced from the same supply you can use as many connections as you like

 

Problems arrive if you have different 5V sources and then connect them as they are both unlikely to be

exactly the same voltage, so you will get current flowing into what is supposed to be a supply output.

 

I think the SDrive Max when wired with both SIO and external USB fried a few unwary peoples

who built their own without a suitable switch.

 

[+Larry]

Thanks, that makes sense with the voltage differential between more than one supply -- e.g. internal supply and external usb.

[Mark2008]

On 5/18/2022 at 1:37 PM, Beeblebrox said:

@Larry  that would make sense being ok if coming from the same 5V line source I guess. I am assuming 2 x separate internal 5V sources would be an issue 

 

 

coincidentally, I own one of those 512k externals, used with an Atari 800XL with 5v PBI mod.  I've never plugged up the 5v into the joystick port....good to know I can haha.   

 

I always wondered why he went with 5v over the joystick port since it always seemed to me something like 5v on usb would solve the problem and keep the joystick port free for two player joystick games or xep 80.    Never thought about the danger of someone unknowingly having 5v pbi - and accidentally second sourcing 5v...interesting