Atari 800 RAM Selection

[Faicuai]

The Axlon 128K RAMdisk did use the same 16K bank region as the XE, just the bank register was different. I suppose you could modify the Axlon by removing its register chip and wiring it directly to some PORTB bits so it acts more like an XE, but what's the point? I think most RAMdisk software already supports the Axlon, no?

 

THANKS for the details (16K-window makes logical sense when actually plugged in a given ram-slot, like #2). FYI, the only AXLON ram-expansion I remember ever using was the one purchased-and-installed on my long-gone Atari 400 (I think it was a 32K board). It is unfortunate that I've always found the 400 too limited, could never enjoy it, and could not preserve it, either.

 

As to what software exploits AXLON (beyond mere RAM-disks), a few days ago I browsed on my Synapse's SynCalc manual, and (accidentally) found it suggested the AXLON ram-boards as recommended expansions (not sure if it actually exploits, though).

[Retro Rogue]

From original post:

 

 

According to Vendel & Goldberg, a software guy, Alan Miller, was responsible for the RAM selection design:

 

Yes, most of the info for that chapter (including the passage you included a clip from) came directly from the Colleen engineering logbooks we were given from Joe Decuir. (He still has most of his engineering logbooks from his time at Atari). That's also why we decided to go with more of a diary/logbook feel for these kind of chapters.

 

Alan is of course famous for being one of the original 2600 launch programmers and later co-founder of Activision.

[awace]

That happens all the time I try to explain something about car problems to my dad and he scoffes it off untill I SHOW him what the problem is then we fix it to gether or he goes online and explaines its way more complicated than it seemed .

I always check for loose cart slots sometimes on my Arcade space invaders Cabinet i would check the board connector witch is a super huge cart slot for the audio board whell finnaly due to a actuall breakage on the other board side the finger board pin came off the (-) 5v line I was like yea because this is what was wrong it was comeing lose all the time making it reboot and act up all the time so i soldered it closer in to a nother hole thru but still reflowed the fingers on the pcb anyway with solder as in 1979 the only people who were gold plating finger boards were Atari LOL Also those GI General Instruments silver pins suck they break off all the time and corode..

most of the time you can pull up a super small amount and get an atari Cart even if its ram or rom to reconnect good..

PS ..

Before my freind said you can jump in high caves with Pitfall II and catch a ballon witch comes after two bat passes and I did not know this and one day I was playing the 800 with a drywall screw in side it so the door could be open and i could unplug the cart leaving the left side on the pcb in but the right side slightly higher and then if i set it up correctly i could push on the cart making chunks and you could walk threw some walls then it would of course screw up the music untill you died of course and fixing it self but sometimes it would swim in places you cant swim lol also the music screws up the same every time and you cant get past the muskrat even if you use save states in emulation but i managed to open up level II a whole nother game inside the 1st game if you get all dudes and the diamond you can will open up a portal door to level II ..

I just the other day noticed a ddr sitck of memory was making chunks on the screen for example virus looking ☺ smiley faces and coloered ansi graphics on the 1st boot screen and i was like hmm this memory stick seems lame I wiggled it and viola the chunks chagned then completly locked up reminds me of REV D atari Rom operating system after we exchanged An atari for a bad rf modulator they updated the 10k rom operating system to differnt version on 400...

I took the DDR memory stick and used a green 3m scrubbie dish scrubbie on it and then blew it off removing the green chunks and viola it worked w out showing those chunks..

 

 

Also You might notice if you play PATHFINDER and

 

 

do this

___________

go here \ ___________

_________

_________ \

 

then opposite so you end up inside the filled boxes you have to do opposite angle

movements

left down right up then left up right down

total exact angle only opposite you need a 8 way joystick or normal atari joystick but slick sticks work the best for this then once you end up inside the blocks go out side the border of the game wall......!!!!!!!!!!!

then you can go up allong the ones you fire to solid then once you go up keep going up w out touching anything exeprt for energy ones you can also get fire hydrent refills but why ..

then keep going up or down and you will actually SEE the internal Atari memory working you can not touch this as instant death but you can watch the page frame video move and the memory move around as graphics its really cool to actually see the memory in action ....

 

I have yet to get the atari 400 memory upgrade but do have the xp sp1 on a pc104 mini single board computer w ape and ape cable and ape shareware witch loads up to the atari ...

I also fixed the tape recorder program recorder this was not easy nor fun as I only out of 3 1/2 units have one that works to rewind and fast forward also there is more than one spring to deal with on the take up wheel and there are more than one belt to replace also I needed to short the audio to the data on the head wilst adjusting the head azimuth but this was easy using music lynard skynard made alignment easy ...

I also noticed if you leave frogger run all night long on xp or xp x64 bit it locks up if you dont use 320x200 mode....

also some of the new german party .atr files will amazingly load onto the atari800 witch is awesome ..

I can if i get time take pictures of the schmatics from DE rE atari and the other internal Atari stuff my dad and his freind used to program emulation of disc drives using cpm loader ...

my favourite thing to do now is burn 2732's with 8k atari 2600 roms i used hackomatic II to change graphics in ...

[+DrVenkman]

What kind of RAM for the Atari is this? I've never heard of it.

 

eBay Auction -- Item Number: 390284769754

 

ClausB: I'll post when I get home.

 

Sorry for the necropost but hey! I have the same board in one of my 800's! The Google was remarkably unhelpful when I tried to look up anything about it. I just happened to run across this old thread tonight for no particular reason.

 

Edited May 17, 2015 by DrVenkman

[+slx]

Is there any difference in usability between Mosaic and Axlon 32K boards?

 

And will 16K + 32K + Axlon 128K actually result in more useable RAM than 16 + 16 + 128?

[+Nezgar]

Take a look at this thread: http://atariage.com/forums/topic/177885-atari-800-ram-selection/?p=2800671

 

Seems the proper configuration is Slot 1: 16K, Slot2: Axlon 128, Slot 3 16K

 

But depending on your 32K board, you might be able to put it in Slot 1, Axlon 128 in Slot 2, and have Slot 3 free (ie for Bit3 80 column board)

[+slx]

Seemed the proper configuration is Slot 1: 16K, Slot2: Axlon 128, Slot 3 16K

 

But depending on your 32K board, you might be able to put it in Slot 1, Axlon 128 in Slot 2, and have Slot 3 free (ie for Bit3 80 column board)

Thanks, it’s not my 32K board yet but was offered on AmiBay, but if 32K are required for Bit3 or similar only, I‘ll pass on that as the probability of finding a Bit3 at a price I‘d be willing to pay seems to be rather low... (and I‘d still have to buy a 60Hz mono CRT to go with it).

 

 

Gesendet von iPhone mit Tapatalk

[+kheller2]

I just found out that a 400 I own has an Austin Franklin ram board.  The 400 is modified for "32k" on the board.  How do you tell the difference between the 32K and 48K versions of the Austin Franklin boards?  The pictures I've seen show 8x4264 ram chips.  Same as this one.  Wouldn't that be 64K possible with additional mods?  Or at least 48K?

[ClausB]

This is the only photo I can find of the AF 32K RAM:

http://www.atarimuseum.com/computers/8bits/3rdparty/ExpansionBoards/Memory/Austin Franklin/index.htm

 

The paper sticker "32K" implies the same board might be used for 48K as well. There are two unpopulated resistors RPD1 and RPD2 which are required for 48K in a 400. The spec sheet below implies that the RAM chips differ between 32K and 48K but I can't find any data for the MT4264-4 RAMs in the photo.

 

Here's another thread about MT4264-4 chips in Intec RAM boards:

 

BTW, MT RAMs are notorious for failing in XL and XE machines. It's ironic to read all the bluster in the spec sheet above about quality and superior design! It's more of an advertisement than a specification.

Edited January 31, 2021 by ClausB

[BillC]

6 hours ago, ClausB said:

but I can't find any data for the MT4264-4 RAMs in the photo

MT4264 are the 64kbit DRAM know for their failure rate in the 130XE/800XL, one of my 130XEs had 2 bad MT4264-20 chips reported by a SYSCHECK 2.1(44 out of 48 red blocks in the OS diagnostics).

[ClausB]

Right. There's a MT4264 datasheet on line but no mention of the -4 version. Could it be a version with some bad bits but still useful as 32K or 48K?

[+kheller2]

5 hours ago, ClausB said:

Right. There's a MT4264 datasheet on line but no mention of the -4 version. Could it be a version with some bad bits but still useful as 32K or 48K?

I’m guessing the -4 mean 250ns and only because I found some very old doc that listed 2 as 150 and 3 as 200 and this agrees with the brochure you posted. Thank you!

 
Also the missing resistors on my RAM board are filled in and the cart port wiring is slightly different from the Atari version, at least on this one 400 I have. 

[Faicuai]

On 3/4/2011 at 7:11 PM, ClausB said:

Depends who made it.

 

The Axlon RAM-Cram 32K board could work in a 400 or in slot 2 of an 800, but not in slot 1 (because they did not follow Atari's scheme, as noted in the first post).

 

The Intec 32K board could work in either slot 1 or 2 but not in a 400 (they didn't quite get it either).

 

The Austin Franklin flyer claimed their 32K board worked in either slot 1 or 2 and in a 400 (maybe they got it, though I have never seen one to verify).

 

I don't know about the Best 32K board.

 

No 32K board could work by itself in the 800 because no slot has all the select lines S0, S1, S2, and S3 (without loopbacks or jumper wires). So, all the boards above required another RAM board in the other slot.

FYI, my Intec does not fire up in Slot-1.

 

It seems only works in Slot-2.

[ClausB]

Which Intec board is that? The one I wrote about is the 32K board with 16 of the 16Kbit chips.

[Faicuai]

55 minutes ago, ClausB said:

Which Intec board is that? The one I wrote about is the 32K board with 16 of the 16Kbit chips.

This one, of course:

 

 

BTW, and related to another board I have here, just wondered (in your opinion) what would ve the easiest or quickest way to identify a malfunctioning SN74LS138N, SN74LS00N or SN74LS09N, without being forced to desolder the latter two...

 

Edited February 1, 2021 by Faicuai

[ClausB]

My Intec is a 1982 model MM1632.

 

An oscilloscope or a logic probe can help find bad chips. Even a DVM.

[ClausB]

On 1/31/2021 at 10:40 PM, Faicuai said:

FYI, my Intec does not fire up in Slot-1.

 

It seems only works in Slot-2.

Took a closer look at my Intec MM1632 and it is not wired the way I wrote in 2011. It is wired like the Axlon, so it would not work in slot 1, like yours. What I wrote in 2011 was based on my notes from back in the day, so that must have been yet another version.

[ClausB]

On 2/1/2021 at 12:15 AM, Faicuai said:

This one, of course:

 

 

Would you post a photo of the backside of that board please?

[Faicuai]

2 hours ago, ClausB said:

Would you post a photo of the backside of that board please?

Here:

 

 

BTW, the problem-board I mentioned you above is this one (started giving me a green screen, recently, and ROMs do not seem faulty, at least on another OS board):

 

 

Don't want to send it to surgery without some basic logic-testing to check if something is obviously wrong....

 

[ClausB]

Thanks. That confirms it's also wired like the Axlon, so no slot 1, like you said.

 

Wow, what is that ROM board? So many switches, so many sockets, and a jumper wire to boot!

 

Did you try flipping each switch back and forth a few times to scrape off corrosion? And reseat the chips?

Edited February 3, 2021 by ClausB

[Faicuai]

34 minutes ago, ClausB said:

Thanks. That confirms it's also wired like the Axlon, so no slot 1, like you said.

 

Wow, what is that ROM board? So many switches, so many sockets, and a jumper wire to boot!

 

Did you try flipping each switch back and forth a few times to scrape off corrosion? And reseat the chips?

Ok, so we sorted out why the Intec-32KB won't launch on Slot-1, but on Slot-2...

 

The other crazy OS-board is the Newell RAMROD... As you suggested, I cycled all DIP-switches, on both panels... no avail. The white-panel is just for defining whether ROMs or EPROMs are used... so only two (reciprocal) settings are documented (the other is just opposite, switch-by-switch of what I set it for = ROM).

 

With the other 4-dip panel, this board also enables 52 KBytes (+4KB ram on $C000-$CFFF, but it does so with 2KB granularity, meaning you could have +2KB ram, +2KB eprom on that very 4KB space). That one also allows to mask RAM off the OS...

 

Here's a pic. during some troubleshooting:

 

It is giving me a green screen (like if I had removed the second I/C on the MoBO, behind the LEFT cart-port). Not sure if it is even mapping the ROMs in the $D800-$FFFF space... so I was wondering which I/C on the bottom-row could be responsible for it... I thought you may be able to deduce it by looking at the circuit-tracks (it is not clear to me, though...) ONLY the far-left is socketed (being the next of the right identical, but all remaining ones are NOT, which means de-soldering, etc.)

 

Those 52 KBytes are very useful. I have a special, wrapped versions of XEP80 Ultra Drivers (Avery) that load up there, and free up all of base ram up to $C668, including E: DL + Buffer relocation up-there (which becomes inactive, thus not interfering with AXLON's $CFFF control register). It was meant to be used on my reference 800 (a barely used CTIA, week-4 1980, that I just got and restored recently):

 

 

That's where the INTEC is for as well, so the BIT3 (which I just finished repairing and restoring) operates as intended with 48KB. The only problem I have with memory on this configuration is that 512KB board that goes on Slot-2 (where the INTEC is). It is a recently made board, that DOES NOT give an extra +16KB for the $8000-$BFFF range... The black-jumper on the RAMROD connects to the 512KB board, when present....

 

Sorry for the long story, but now you have the whole picture....

Edited February 3, 2021 by Faicuai

[ClausB]

Yes, it should work in slot 2 with 16K in slot 1.

 

I'll look at your ROM board photos and try to deduce something. I'll need a photo of the backside.

 

The 512K board, is that the SRAM board recently sold here? I got one of those and am planning to mod it to cover 8000-BFFF. I'll let you know how that goes.

Edited February 3, 2021 by ClausB

[Faicuai]

5 minutes ago, ClausB said:

Yes, it should work in slot 2 with 16K in slot 1.

 

I'll look at your ROM board photos and try to deduce something.

 

The 512K board, is that the SRAM board recently sold here? I got one of those and am planning to mod it to cover 8000-BFFF. I'll let you know how that goes.

Yes sir, that's the one (a tiny one sold here, which misses the point on that address range, being otherwise useful and compact).

 

You may want to also consider that both the 512KB expansion and the INTEC-32KB (for some strange reason) BLOCK the right-cart port (I can't boot right-carts when those boards are present on the bus...) Very strange, but confirmed on my production units, as well as my test / troubleshooting bed.

Edited February 3, 2021 by Faicuai

[ClausB]

Please post a photo of the ROM board backside.

 

Odd about the right cart. They should handle that. Even with the standard Atari OS board? On multiple 800s you say? How many right carts have you tried?

[Faicuai]

13 minutes ago, ClausB said:

Please post a photo of the ROM board backside.

 

Odd about the right cart. They should handle that. Even with the standard Atari OS board? On multiple 800s you say? How many right carts have you tried?

Here you, a bit closer back-side and front:

 

 

 

 

 

Yes, I agree those RAM expansions should not be blocking with Right-port, but MokeyWrench-II fails to boot there.

 

I wish I had a flashable  / programmable right-cart, self-disappearing, addressable and responsive to $D5XX I/O area,  and supporting rom-banking... We could certainly put it to good use (including testing), and leave it there plugged, permanently. Even the XEP80 and BIT3 could be booted on-the-fly, on-demand, from that right-slot baby...

Edited February 3, 2021 by Faicuai