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Cool Display from HP — Parallax Forums

Cool Display from HP

TimCTimC Posts: 77
edited 2006-07-11 19:25 in General Discussion
Hi,
I have been playing around with these dot matrix displays from HP. They have lots of flexibility and look great. Most of the time they are expensive but occasionally they show up on Ebay cheep. I got this one, SPI interface, from an auction that is still going on (search: HCMS-2911)

I have included all the code to get this pup to display your keystrokes.

Regards
Tim
hcms2911.JPG
BS2
BS2
DSPSpi.BS2
8K

Comments

  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-02-24 05:49
    Tim,

    ·· This is a nice display and I have purchased many items from the guy selling these on eBay now.· But I need to move this thread to the Sandbox Forum since it's off topic here.· For those interested though:

    http://stores.ebay.com/Experimenters-Discount-Warehouse

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • TimCTimC Posts: 77
    edited 2006-02-24 12:53
    Thank You Chris.

    One thing to add is that you do not get a character ROM inside these chips. So you need to add a fair amount of code just to display a single character.
    The advantage is that you can make your own character set.
    The attached code above adds all the common characters in a 5x7 matrix just like what's inside most LCD's

    Regards
    Tim
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2006-02-24 13:38
    Looks Excellent, TimC.·
    Could you U/L a schematic to go with it?
  • TimCTimC Posts: 77
    edited 2006-02-24 14:58
    Since there are no extra parts, all wire either go to the stamp or for power.
    Here are the connections to the display:

    DISPLAY PIN - PARALLAX PIN (CONTROL FUNCTION)
    Pin3 - +5
    Pin7 - Gnd
    Pin10 - +5
    Pin14 - P1 (Data IN)
    Pin15 - P6 (RS)
    Pin17 - P2 (Clock)
    Pin18 - P5 (CE)
    Pin19 - P8 (Blank control)
    Pin20 - Gnd
    Pin21 - +5
    Pin22 - +5
    Pin24 - P7 (Reset)
    Get the Data Sheet you will need it:
    www-mtl.mit.edu/Courses/6.111/labkit/datasheets/HCMS-2973.pdf

    Regards
    Tim
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2006-02-24 14:59
    That's good to know...I had assumed it was character.· Still, I could see several practical uses.· Cost could be a factor though with it not having it's own characters.

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    Chris Savage
    Parallax Tech Support
    csavage@parallax.com
  • Matt BattleMatt Battle Posts: 172
    edited 2006-02-24 17:05
    Some what off topic but what board is the HCMS-2911 connected too? Just curious.

    -Matt
  • TimCTimC Posts: 77
    edited 2006-02-24 18:57
    A Parallax AppMod Bread Board.

    Parallax stopped making them years ago mad.gif
  • Matt BattleMatt Battle Posts: 172
    edited 2006-02-24 19:11
    Well, they need to bring it back!! mad.gif I wonder if I can find them on the internet somewhere?

    -Matt
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2006-02-24 19:21
    It was never a good seller and won't be again.... Sorry, but if we stock our shelves with products that don't move it hurts everybody.

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    Jon Williams
    Applications Engineer, Parallax
  • TimCTimC Posts: 77
    edited 2006-02-24 20:11
    I forgot about the The Parallax Professional Development Board. So I should not be upset about not being able to get more AppMod Bread Board's

    I checked for the version of display that includes the character ROM but the only one I could find was the HDSP-21xx series???. They have a different interface and use a LOT more pins and more $$

    These would make great displays if they were SPI and have a char ROM.
    Both versions have a lot of flexibility in power consumption and are fully stackable.

    Regards
    Tim
  • Kenny GardnerKenny Gardner Posts: 169
    edited 2006-02-24 20:12
    I wonder if the reason the Breadboard AppMods weren't good sellers is because they cost $25? I've got 5 of them that I got cheap off of eBay. I wanted more but I would never pay $25 for them.

    And yes, Dakro is a good source of electronics on eBay. He had some VFD's real cheap. I put some Scott Edwards backpacks ·on them and they are every bit as good as the more expensive Matrix VFD's.

    Kenny



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    --

    Kenny Gardner
    GAP Development Company
    http://www.gapdev.com/
    ·
  • GadgetmanGadgetman Posts: 2,436
    edited 2006-02-25 12:33
    TimC said...

    One thing to add is that you do not get a character ROM inside these chips. So you need to add a fair amount of code just to display a single character.

    The Propeller comes with a Character ROM...

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    Don't visit my new website...
  • TimCTimC Posts: 77
    edited 2006-02-26 01:00
    Gadgetman,
    The Propeller uses a 16x32 matrix, the HP display uses a 5x7 matrix, so each ROM map is very different. In addition the entire HP display is a 320bit shift register so the loading of each character is a different process with each character code.

    All the code needed to make the HP Display work IS INCLUDED below the JPG at the top of the thread.

    What I meant to say before was, without all the pre-written DATA statements anyone who wants to write their own display program has a lot of work to do designing each character.

    Regards
    Tim
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2006-07-11 19:25
    · Soldered up my display on some experimenter board·with a SIP header, plugged into H-W-B.
    · Works for me.
    · Thanks again, TimC.
    · (Pic attached -- Through the Aiptek Darkly.· Sorry.)

    · Post Edit -- better pictures, through better lighting, some Katakanas.

    Post Edited (PJ Allen) : 7/11/2006 10:47:42 PM GMT
    TimC_disp.JPG
    580 x 452 - 30K
    HP_SPI_better.JPG
    1248 x 960 - 231K
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