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Need help!

Brandon C.Brandon C. Posts: 106
edited 2008-10-27 15:06 in Propeller 1
Hello, I'm new here! I'm considering getting the propeller chip or two, but I do have a few questions though:

1. If I get the Demo board, what other part(s) does it require?

2. My plan is to make something sorta like a computer, only just not as advanced. I want to know if
its possible to hook up 2 propeller chips together, and have them communicate with eachother.
e.g, lets say i may want to make a video card for it, and let that do all the hard work and the
main processor just has to give the video card basic information, such as the resolution, and the
video card can receive that information and do all the hard work. is this possible?

3. How would I add RAM to it? What parts would i need?

4. When I read that the chips clock can be changed, what does it mean? overclocking it? or am I just comfused?

Thanks,

Help is appreciated.

Post Edited (Mr. Dr. Professor) : 10/20/2008 10:57:23 PM GMT
«1

Comments

  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2008-10-20 23:03
    I'll address #2

    The creation of a mini computer from a Propeller is very possible.
    Some of us were drawn to the Propeller because of this.

    Check out these links.

    PropDOS (and related software)
    http://forums.parallax.com/showthread.php?p=683157

    PropGFX (A Propeller addon video card {made from another Propeller})
    www.propgfx.co.uk/forum/Blah.pl?b-PL/

    Also, since you are new, you might appreciate this list..
    www.warrantyvoid.us/projects.html

    Welcome to the forums..

    OBC

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    New to the Propeller?

    Getting started with a Propeller Protoboard?
    Check out: Introduction to the Proboard & Propeller Cookbook 1.4
    Updates to the Cookbook are now posted to: Propeller.warrantyvoid.us
    Got an SD card connected? - PropDOS
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-20 23:11
    1) You need a power supply (7.5V 1A) and at least a mini-USB cable. You'll need to download the Propeller Manual and the Propeller Tool. If you get the Starter Kit rather than just the Demo Board, you'll get these items included as part of the kit. If you want to use a TV monitor or VGA monitor, you'll need standard cables. If you want to use a PS/2 keyboard and/or mouse, you'll need to have those.

    2) It's been done. Look at forum message threads regarding the Prop-GFX which is a Propeller-based graphics processor meant to be used with a separate Propeller or other microcontroller.

    3) You can add additional serial EEPROM or RAM (or FRAM which behaves somewhat like both) easily. I2C-based memory is the easiest to add and there are several I/O drivers that can use it. Keep in mind that this memory DOES NOT extend the existing RAM or ROM. There's no way to do that. You can also add an SD card. All that requires is an SD card socket and optionally 4 pullup resistors. The I/O drivers for this are in the Propeller Object Exchange library. The SD card can be up to 2GB in size and uses a standard DOS/Windows FAT (FAT16) file system.

    I2C memory can be added just by wiring the parts in parallel with the existing EEPROM although the Demo Board doesn't have provisions for accessing the device pins used for the existing EEPROM. You can use any other even/odd I/O pin pair with the existing drivers for another I2C bus.

    4) The chip is not designed for "overclocking". It will work if you're careful about the power supply voltage (at the chip) and the operating temperature. The Propeller's datasheet has information on maximum system clock speeds vs. supply voltage and temperature. The system clock works at multiples of the crystal frequency used and that is configurable by a program. Read the Propeller manual for details of this and the internal RC clocks.

    Post Edited (Mike Green) : 10/20/2008 11:16:22 PM GMT
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-20 23:18
    Wow, Thanks for the quick reply!smile.gif· And I didnt know there where so many ideas just like mine. tongue.gif
    I actually have that same Idea with the Operating system. I think its a pretty cool thing to do. as I've always wanted to do that with computers, but I have no idea how its done.

    Oh, and mike, I dont know that much about electionics right now because im only 13, so could you please explain to me what an I2C is? Sorry,
    I'm trying to learn as much as i can right now.




    Post Edited (Mr. Dr. Professor) : 10/20/2008 11:26:25 PM GMT
  • Paul BakerPaul Baker Posts: 6,351
    edited 2008-10-20 23:32
    I2C is a communication protocol used between chips. The vast majority of chips that use I2C are some form of non-volitale memory (memory that keeps it's contents after powering down), but there are other devices which use the protocol as well. I2C uses 2 lines to communicate, SCL (Serial Clock) and SDA (Serial Data). SDA is bidirectional (meaning it is used to communicate both ways).·

    In general if there is something that is completely new to you, a really good first place to check is wikipedia which generally does a good job at summerizing a subject. The I2C page is located here: http://en.wikipedia.org/wiki/I2c·

    The information presented on that page is a lot more detail than you really need to know. There are several objects free for download from http://obex.parallax.com that make talking to an I2C chip quite easy (one of them was written by Mike Green, so the author would be able to help you here if you ran into problems (Sorry for volunteering you like that Mike)).

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Paul Baker
    Propeller Applications Engineer

    Parallax, Inc.

    Post Edited (Paul Baker (Parallax)) : 10/20/2008 11:39:06 PM GMT
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-20 23:54
    Does Parallax sell I2C chips?
  • $WMc%$WMc% Posts: 1,884
    edited 2008-10-20 23:54
    Mr. Dr. Professor

    I would highly recommend The Propeller Pro.Development Board.(It's Parallax part# 32111). It has everything Your lookin for. RCA "NSTC" video/DB-15 "VGA" video ,keyboard,mouse. An on board USB driver for programing (that hooks up to a host PC). A DB-9 RS232 AUX. serial jack. A large BreadBoard area to place that 2nd Propeller chip You mentioned.Plus a lot of other things.
    But if Graphics are all Your lookin @,,Take A look @ the HYDRA.It has the added MEM. you spoke about and is geared toward video/gamming.

    See ya in the next thread.

    _____________________$WMc%__________________out_____________
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-20 23:54
    Does Parallax sell I2C chips?
  • Paul BakerPaul Baker Posts: 6,351
    edited 2008-10-21 00:05
    We have 1: http://www.parallax.com/Store/Sensors/CustomKits/tabid/134/txtSearch/i2c/List/1/ProductID/453/Default.aspx?SortField=ProductName%2cProductName

    But I would really recommend getting one from many of the major chip supply houses (Mouser, Digikey, Jameco, etc), You should look for one in a DIP package, since you can put it in a breadboard for easy wiring. The only other important thing to know is how big you want the memory, the one that comes with the demo board is 24LC512 (32K bytes (256K bits)). You should get as large as this or greater. If you type I2C eeprom in one of the companies search engine, it will take you to the chips they offer (I recommend Mouser for small orders since they don't charge a small order surcharge).

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Paul Baker
    Propeller Applications Engineer

    Parallax, Inc.

    Post Edited (Paul Baker (Parallax)) : 10/21/2008 12:10:32 AM GMT
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-21 02:31
    How did I post twice?

    lol sorry about that.

    $WMc%, I took a look at the pro version before, but I thought it was kindof expensive.
    And I think it has a little TOO much on it. its more than I need. And the HYDRA, I
    originally was on xgamestation.com looking at that, but then I took a look at parallax,
    and I liked the Prop demo board better.

    Post Edited (Mr. Dr. Professor) : 10/21/2008 2:38:50 AM GMT
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-21 02:54
    Parallax sells a few sizes of memory chips that use the I2C protocol. The company that developed this protocol (Philips) has a subsidiary (NXP) that makes a variety of chips that use it and they have lots of information about I2C on their website ([url=http://www.nxp.com/#/homepage/cb=[t=p,p=/50807/41735]|pp=[t=pfp,i=41735]]www.nxp.com/#/homepage/cb=[noparse][[/noparse]t=p,p=/50807/41735]|pp=[noparse][[/noparse]t=pfp,i=41735][/url]). Other companies like Microchip, Dallas/Maxim, TI, and others also make I2C chips. Do start with the Wikipedia article on I2C. That will give you a good introduction.
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-21 19:00
    Oh, I forgot I also have another question:
    5. Whats· the max resolution the Propeller can support? I have a 1920x1200 monitor,
    could I set the prop to use this resolution?
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-21 19:44
    No

    There is a 1600 x 1200 pixel driver downloadable from the Propeller Object Exchange. This requires 6 cogs for the video driver and uses about 16K for the display buffer. It's capable of displaying small areas of graphics which require further memory at roughly 4 pixels per byte.

    Post Edited (Mike Green) : 10/21/2008 7:53:53 PM GMT
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-21 19:58
    So If i add RAM, I would be able to go higher than that?

    Yet another example of a use of a video card, I could have it display at a high resolution without it interfering with the
    main processor.
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-23 16:18
    Ok, I took a look at Mouser. If I'm correct, this is what I need along with an I2C chip?

    http://mouser.com/Search/ProductDetail.aspx?qs=Z0HAwyWrFkw0HCxrN5WMtQ%3d%3d
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-23 17:13
    I suspect you won't be able to go higher than the 1600 x 1200. That's already using 6 cogs for the video processing and you'd need to add more cogs to get the throughput, let alone the extra memory. The video rate needed is 20% higher than that for the 1600 pixel width line. Keep in mind that this driver was developed by the Propeller's designer after producing several other VGA drivers of increasing resolution. It uses nearly all of the Propeller's capability to work and leaves very few resources for anything else. I don't want to discourage you, just that it would not be a simple thing and you'll need to understand the Propeller and its instruction set very thoroughly.
  • Paul BakerPaul Baker Posts: 6,351
    edited 2008-10-23 18:37
    The Ramtron part you linked to is a parallel FRAM, not an I2C FRAM, an example I2C memory from them is the FM24C512.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Paul Baker
    Propeller Applications Engineer

    Parallax, Inc.
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-23 19:36
    Another question, is it possible to interface the Propeller with a Hard Drive? would I need a type of controller?
    I have a 5400RPM 100GB laptop HDD, and I know I probably will not find 100GB worth of stuff for it, but i think it would make a
    neat experiment.
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-23 20:45
    Others have asked this question before. It's possible, but not particularly useful. The IDE/ATA interface requires a lot of I/O pins. Best is to use an SD card with the existing drivers. You can also use the Vinculum USB host chip (like the Parallax datalogger) and a USB HDD.
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-23 22:00
    You mean a External HDD? I have an enclosure for the notebook HDD, and its USB. something like that?
    ·
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-23 22:20
    Yes. The Vinculum chip (in the Parallax USB memory stick datalogger and other similar devices) can control any kind of USB mass storage drive including an external HDD with a USB interface.· Download the manual and the Vinculum documentation from Parallax's store webpage for the datalogger.
    ·
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-23 22:40
    Thanks mike! With all this stuff being supported by the propeller, I'm now wandering if its possible to interface a laptop screen? I wouldnt doubt that you'd say yes to this too.turn.gif
  • Paul BakerPaul Baker Posts: 6,351
    edited 2008-10-23 22:58
    It was just brought to my attention by a customer (Thanks Jason) that we actually sell a few more I2C chips (including·the 32K-byte EEPROM we use in the Propeller Education Kit): http://www.parallax.com/tabid/614/List/0/CategoryID/79/Level/a/SortField/0/Default.aspx


    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Paul Baker
    Propeller Applications Engineer

    Parallax, Inc.
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-23 23:05
    Can these be connected to eachother?
    I wanted to get the 32KB one, but its all out. Maybe I should just connect a few· 16Kb chips together?

    Thx Paul!

    Edit:

    Oh, and Mike, here are some pictures of what i was talking about:

    The Screen
    http://www.majhost.com/gallery/DarthToa/Computers/img_0695.jpg


    The Cable
    http://www.majhost.com/gallery/DarthToa/Computers/img_0694.jpg

    As you can see, the cable looks like it has a lot of pins on
    it. So If i do connect it, it looks pretty complicated.

    Post Edited (Mr. Dr. Professor) : 10/23/2008 11:14:47 PM GMT
  • Oldbitcollector (Jeff)Oldbitcollector (Jeff) Posts: 8,091
    edited 2008-10-23 23:17
    You would need to tap into the video chip that feeds that screen in order to connect it to the Propeller.
    (almost impossible task) I think a couple people here have attempted it without success.
    Better solution would be just to output to a standard VGA flatscreen.

    OBC

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    New to the Propeller?

    Getting started with a Propeller Protoboard?
    Check out: Introduction to the Proboard & Propeller Cookbook 1.4
    Updates to the Cookbook are now posted to: Propeller.warrantyvoid.us
    Got an SD card connected? - PropDOS
  • JasonDorieJasonDorie Posts: 1,930
    edited 2008-10-23 23:19
    If you're using them yourself, connecting more than one to the same Prop will work, but you'll need two Prop I/O pins per chip.

    You won't be able to boot from them, as they're accessed individually, not as a 'sum total'.· The Propeller boot loader wouldn't know to pull 1/2 the data from one and then the other.

    SparkFun also sells the 32Kb I2C chip (http://www.sparkfun.com/commerce/product_info.php?products_id=525).· You're better off getting them from Mouser or another supplier, since they're cheaper: (http://www.mouser.com/Search/ProductDetail.aspx?qs=wJ05WdDZ4qSE4f7vrKy23Q%3d%3d).

    Just do a Mouser search for I2C EEPROM.

    Jason
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-23 23:20
    @ OBC
    I'm guessing that your probably right considering I have no idea what your talking about.

    @ Jason
    I'm not going to be booting from them, but using them as RAM.

    Post Edited (Mr. Dr. Professor) : 10/23/2008 11:26:22 PM GMT
  • hippyhippy Posts: 1,981
    edited 2008-10-24 00:00
    I'm not going to be booting from them, but using them as RAM

    Using I2C EEPROM as RAM might not be such a good idea; limited write lifetime plus slow write times may get in the way there. FRAM would be better but might not be ideal, depends on the actual application.

    It is possible to use a Propeller chip as a 32Kx8 I2C RAM but I'm not sure what the maximum bus speed / throughput would be.

    Interfacing to an IDE Hard Disk isn't as bad as it could be nor necessarily I/O hungry if you use an 8-bit bus and forgo half the disk capacity and don't need to be compatible with any other file system. Perhaps the hardest part would be interfacing the 3V3 Propeller to what are usually 5V drives.
  • Mike GreenMike Green Posts: 23,101
    edited 2008-10-24 00:27
    Ditto on OBC's opinion. You do not want to try to interface to a laptop display. It requires too many resources (pins, memory, speed with tight timing) and you'd need to get detailed documentation on signals, timing, etc.

    Stick to a VGA display. Stick to either an SD card for mass storage or something like the Vinculum with a USB memory stick. There's plenty of work and the associated learning starting from there.
  • Brandon C.Brandon C. Posts: 106
    edited 2008-10-24 20:02
    So if I wanted something to use for a GPU, what would I use besides another propeller?
  • OwenSOwenS Posts: 173
    edited 2008-10-25 10:11
    Mike Green said...
    Ditto on OBC's opinion. You do not want to try to interface to a laptop display. It requires too many resources (pins, memory, speed with tight timing) and you'd need to get detailed documentation on signals, timing, etc.

    Never mind the fact that if you get the timing wrong the things boil devil.gif

    (This is the reason that the X.Org nVidia, Intel and ATi graphics drivers ignore any custom frequency settings on laptop screens)
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