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(Hardware) Project of the 'calendar quarter'

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I've been looking carefully at the board now that I have the original pretty much replicated and enhanced. I discovered some interesting things by doing so, specifically, that the board may be extended to a somewhat larger size by simply replacing two chips (the memory chips) and running the necessary additional traces to connect two more address lines. What does that give us? How about a 4 Meg SAMS board. . .using BQ4017 or DS1270Y memory chips.I will probably still do a run of the replicated boards--but I may look deeper into this once I have done so, especially if there is sufficient interest in a larger SAMS board..

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I've been looking carefully at the board now that I have the original pretty much replicated and enhanced. I discovered some interesting things by doing so, specifically, that the board may be extended to a somewhat larger size by simply replacing two chips (the memory chips) and running the necessary additional traces to connect two more address lines. What does that give us? How about a 4 Meg SAMS board. . .using BQ4017 or DS1270Y memory chips.I will probably still do a run of the replicated boards--but I may look deeper into this once I have done so, especially if there is sufficient interest in a larger SAMS board..

At 8 Meg we are close to loading a GUI type of OS using the SAMS. Of course using a Joystick instead of Mouse as the Joystick does not need interrupts to work like the mouse.

Then again we can not run multiple programs at the same time, but a 4 meg would make a kick ass game load.

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How about a 4 Meg SAMS board. . .

 

The more memory the merrier, especially if it does not appreciably raise the selling price by too much, because purchasing one of these boards is pretty much going to be "an act of faith" that useful things will be written and/or modified for it. I feel that with THAT kind of memory, it'll inspire more people to try to exploit it.

 

I wonder, a 4meg SAMS + UberCart + F18A = :-o ?

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I've spent the day playing with the layout. It was actually pretty easy to implement the mod I envisioned, so I now plan to make a few of these to test them out--as 4 Megabyte boards that can be downshifted to 1 Megabyte boards by those wanting to use 512K chips instead of the 2 Meg chips used in the upgrade.

post-27541-0-85697300-1456522007_thumb.png

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I've spent the day playing with the layout. It was actually pretty easy to implement the mod I envisioned, so I now plan to make a few of these to test them out--as 4 Megabyte boards that can be downshifted to 1 Megabyte boards by those wanting to use 512K chips instead of the 2 Meg chips used in the upgrade.

 

Can't wait to see the real thing completed, she's gonna be a beauty!

post-27541-0-85697300-1456522007.png

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On Thierry's TI Tech Pages he has notes on an extension to 8MB and 16MB.

How hard would that be to implement with the current board layout? Or would it require a total re-design?

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It would require serious redesign to extend it that far. I actually built one of his 16 Meg boards a while back, but the computer fails to recognize the board for some reason. I found a few issues in his original layout and corrected them, but there are apparently some additional ones that I haven't been able to track down and quash yet. That is why I went this route. . .

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I'll know soon enough whether or not these boards work. I ordered a few test articles this morning, which I should have in hand for assembly/test in a few weeks. Now it all depends on my work schedule to see how soon I'll actually be able to build one. . .

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I've been looking carefully at the board now that I have the original pretty much replicated and enhanced. I discovered some interesting things by doing so, specifically, that the board may be extended to a somewhat larger size by simply replacing two chips (the memory chips) and running the necessary additional traces to connect two more address lines. What does that give us? How about a 4 Meg SAMS board. . .using BQ4017 or DS1270Y memory chips.I will probably still do a run of the replicated boards--but I may look deeper into this once I have done so, especially if there is sufficient interest in a larger SAMS board..

 

Those chip designations, come back as Non-volatile SRAM... Are their cheaper volatile forms you are looking at?

 

[email protected]

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The 2 Meg chips are only available as nonvolatiles so far as I've been able to find--but if you downshift to the 512K chips, you can use nonvolatiles or standard SRAM chips with the board. That was actually my main reason for including the downshift capability. . .and one of the 2Meg chips costs about the same as three of the 512K chips, so they are effectively a bit cheaper per bit.

Edited by Ksarul
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SO, if the board does use NVRAM, does this effectively make it a semi-permanent RAMDisk and keeping information between power on sessions? That would be AMAZING!

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SO, if the board does use NVRAM, does this effectively make it a semi-permanent RAMDisk and keeping information between power on sessions? That would be AMAZING!

The SAMS is a MEMORY Board not a RAMDISK.

 

This GAME uses 336K of the SAMS.

Edited by RXB
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SO, if the board does use NVRAM, does this effectively make it a semi-permanent RAMDisk and keeping information between power on sessions? That would be AMAZING!

 

I've read about back in the days of CORE memory, you could turn a machine off and later when you turned it back on you would start up right where you left off. Apparently more than one computer was delivered to their new owners with a version of Space War in memory.

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The SAMS is a MEMORY Board not a RAMDISK.

 

 

thanks for the info. is it the same for:

 

- Asgard Memory System (AMS)

- Thiery Nouspikel´s Hyper-AMS (HAMS)

?

 

Are there any cards with a "combination" of RAM-Expansion AND RAM-Disk ?

 

thx for any info

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SO, if the board does use NVRAM, does this effectively make it a semi-permanent RAMDisk and keeping information between power on sessions? That would be AMAZING!

 

Effectively, yes. Non-volatile SRAM (nvSRAM) does, indeed, retain its storage after power is removed. However, you cannot really call that memory a RAMDisk unless it is accompanied by a relavent DSR. That notwithstanding, your point is well-taken.

 

...lee

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See, that's my thought: The hardware is just a memory expansion, but with the right software, it could function as a ramdisk and, as long as there was an option to not re-initialize the disk at boot up, you should be able to retain data between sessions.

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See, that's my thought: The hardware is just a memory expansion, but with the right software, it could function as a ramdisk and, as long as there was an option to not re-initialize the disk at boot up, you should be able to retain data between sessions.

RXB version 1005 had a built in RAM disk that used a GPL DSR and turns the SAMS into a RAMDISK. (Just the Lower 8K from XB)

 

That probably means that ABOOT would have to be re-written as well.

Aboot or MENU only works with Supercart RAM but BOOT could work off of DISK or GRAMKART or PGRAM or some other GRAM device.

 

These video include a SAMS RAMDISK demo and other features of RXB using he SAMS. The demo run many Assembly Lower 8K utilities all from one XB program.

 

 

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Sorry, Rich, but your information is only partially correct. Funnelweb has two modes - 40-column which uses standard VDP and 80-column which uses the expanded VDP of a 9938/9958. It does not use a SAMS card in any way.

Also, ABOOT works very nicely when loaded from a RAMdisk. I think you are confusing it with ASEA which is for EA Supercarts only (refer to the docs).

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It appears I should have been reading the forums more as I just found this thread. I would be interested in one of the new redesigned boards as well!

 

Thanks Ksarul!

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Once someone updates a SAMS to a 4 Meg Version or bigger I can modify RXB to take advantage of it.

As all of this memory management is done from GPL in RXB, it does a better job then Assembly as memory management is never in danger of being corrupted like in Assembly.

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So I am confused about the 32k ram project.. is the resistor required? I see that it is on the completed boards in the photos. I assumed if you don't want a on/off switch you don't need it. Am I wrong?

 

Greg

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