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memory options — Parallax Forums

memory options

El PaisaEl Paisa Posts: 375
edited 2006-07-14 15:50 in Propeller 1
Obviously memory (ram,eeprom) is a major limitation of the Propeller.

If I remember correctly the max memory (ram,eeprom) is limited to 32kbyte each.

Also I understand that Andre' have been working in ways to increase the memory limits by page switching.

Parallax have any plans to extend the memory of the Propeller?

Is there any hope for the near future?

Comments

  • LarryLarry Posts: 212
    edited 2006-07-14 02:24
    el Paisa said...
    Obviously memory (ram,eeprom) is a major limitation of the Propeller.

    NGAAAHHH!!


    No paging, Please! One of the main reasons I was attracted to the Prop was to avoid the paging necessary for 8bit MP's.
    I think that if Chip had put a Gig of ram in the thing, someone would ask for two Gigs.
    Maybe it's time to consider doing your task with a bank of Intel core Duo's or something. How about a half dozen Intel Mac's networked?

    I think the Prop has incredible bang for the buck that hasn't even been tapped yet.
    Ask for more Ram when the chip has been around and folks have done everything there is to do with it.

    mumble mumble

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  • El PaisaEl Paisa Posts: 375
    edited 2006-07-14 03:02
    Larry,
    Since the begining, the memory limitation has been addressed.
    look at this http://forums.parallax.com/showthread.php?p=580256
  • hammerhead74000hammerhead74000 Posts: 58
    edited 2006-07-14 03:11
    >> someone would ask for two Gigs

    Umm... actually, could I get three? burger.gifturn.gifburger.gif

    What, me, a memory hog? freaked.giflol.gif



    Actually, for a high-end "turboprop" a few megs of hub memory should be sufficient (I'm thinking of frame-buffers for machine vision applications in particular)... however, I suppose one could bring out the whole 32-bit address & data bus on a 144qfp (it would only take 66 pins for a non-muxed bus, leaving 70 or so for general-purpose IO).


    smile.gif
  • LarryLarry Posts: 212
    edited 2006-07-14 03:21
    Well, maybe EEPROM has been discussed.

    Lets actually build some stuff before we start demanding more RAM. Besides, I wanna see some neat workarounds first-(smile)

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  • Mike GreenMike Green Posts: 23,101
    edited 2006-07-14 03:33
    I'm pretty sure the toughest external memory usage would be for video buffering. The question is whether devoting 8 pins for a data bus and a couple of counters (for sequential addressing) that can be loaded from the data bus (for a total of 12 to 16 pins) could take care of this without using too many pins. Sequential addresses could be read into a cog in only 2 or 3 instruction times (which is faster than getting them from the hub).

    For slower (serial) external memory storage, the RAMTRON chips could be quite useful and only need 2 lines. I think you can hang 8 on an I2C bus for a total of 256K bytes. If you need cheap, but not write speed, regular I2C EEPROM also works. With a couple of more pins, you can also use SPI RAMTRON or EEPROM chips.
  • ciw1973ciw1973 Posts: 64
    edited 2006-07-14 08:16
    We're all way too memory hungry these days. Part of the challenge of *any* microcontroller type work for me is the limitations it imposes and the fun of overcoming them.

    With the Propeller, we've been given something which is novel, and amazingly powerful, and has more memory than the vast majority of other microcontrollers out there. In fact, each COG is roughly equivalent to a low end PIC or AVR. And yeah, I know there are controllers with 96K of memory or more, but such things are few and far between.

    You need to stop thinking about the chip as a PC replacement, and more as one of the most fun and exciting pieces of hardware there's been in the past few years.

    I'm currently working on a design for a fully bitmapped GUI, with true moveable windows and a mouse pointer which will provide much of the functionality of Windows, but using very low resources, such that what the Propeller has onpchip will be sufficient. I also plan to add keyboard buffering, multiple serial ports and some basic sound generation. The idea is to make the Propeller into a kind of SPI controlled super-peripheral for use with embedded ethernet controllers.

    I'd been working on a design using an FPGA, so have the vast majority of it is already figured out, and I'm now wrestling with the finer details of implementing it using the Propeller. I've not got my Demo Kit the hardware yet, so it's still on paper, but for me the intellectual challenge is what I love the most.
  • APStech-AttilaAPStech-Attila Posts: 38
    edited 2006-07-14 12:04
    Larry:
    ·Personally I hate paging as much as you hate it.

    FORTUNATELY
    ·The Propeller runs code from RAM! And the RAM can be rewritten on the fly!
    ·I have an idea where paging will not be a suffering. (I am not paging a part of the memory, but paging the complete 32k memory! <Actually 31k, 1k reserved for intertask comm.>) This could not be a solution to all memory problems, but could help·for·some applications.

    ·No compiler modification, no extra test equpment, as my soultion is similar to exchanging the complete BOOT EEPROM and rebooting the system. http://forums.parallax.com/showthread.php?p=596171

    Hope you'll like the idea.

    ·Attila
  • Ym2413aYm2413a Posts: 630
    edited 2006-07-14 15:50
    My problem isn't really with paging the 32k RAM.
    I don't think I've ever really done a lot of low level programming on platforms that didn't use paging and memory mapping.
    So I'm pretty much used to it.

    What's wrong with having a 128k EEPROM and swapping things in and out as you need them?
    Lets face it, most of the time a program never needs access to all of its data at once.

    Although a 640x480 color frame buffer would eat up all of your RAM really fast. (lol)
    Then again it's amazing that the propeller (as a microcontroller) can even generate such video without any extra hardware!
    Try doing that with a PIC.
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