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BASIC Stamp Video Output — Parallax Forums

BASIC Stamp Video Output

Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
edited 2010-03-07 18:32 in BASIC Stamp
Parallax has announced the Propeller Backpack, which comes ready to deploy out-of-the-box as a video character terminal for your BASIC Stamp applications. Without doing any Propeller programming, this tiny module gives you windowed, multi-color, programmable-size character output to any NTSC video monitor. Here's what a typical setup might look like:

attachment.php?attachmentid=65690

The video output comes from the center pin of a 1/8" stereo phone jack. Various phone-to-RCA adapters are available (e.g. RadioShack #274-897) for easy interfacing to a video monitor.

Here's a typical PBASIC program for displaying "Hello, world!":

' {$STAMP BS2}
' {$PBASIC 2.5}

io      PIN 15          'Propeller Backpack pin number.
baud    CON 84 | 32768  '9600 baud OPEN.

LOW io                  'Reset the Propeller Backpack
PAUSE 500
INPUT io

PAUSE 2000              'Wait for it to come out of reset.

SEROUT io, baud, [noparse][[/noparse]"Hello, world!"]


And here is what the output looks like:

attachment.php?attachmentid=65692

It's also possible to upload canned Propeller software to the Propeller Backpack via your BASIC Stamp and the same 3-pin connection, as well as to write your own Propeller programs for it, should you choose to do so.

-Phil
BOE_to_Backpack_video.jpg
648 x 621 - 78K
Backpack_hello_world.jpg
540 x 421 - 37K

Comments

  • NWCCTVNWCCTV Posts: 3,629
    edited 2010-03-02 02:13
    WOW!!! I must say this is way cool. I have an idea for an invention and this will help in the developement of it.
  • ercoerco Posts: 20,257
    edited 2010-03-02 03:15
    I take it my Hitt Consulting SX Video Module is now a rare and valuable collector's item...?

    FWIW, I still love the SX Module's Commodore 64-type graphics! [noparse]:)[/noparse]

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    ·"If you build it, they will come."
  • silverbacksilverback Posts: 40
    edited 2010-03-02 22:50
    how many i/o Pins can be accessed on the Prop backpack? If any.

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    If you convince yourself that something is impossible before you even try; you are sure to prove yourself right.
  • hover1hover1 Posts: 1,929
    edited 2010-03-02 23:55
    The documentation on the bottom right of the product page·tells all.

    http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/backpack/List/0/SortFied/4/ProductID/602/Default.aspx

    If you have any questions about the documentation, please ask.

    Jim
    silverback said...
    how many i/o Pins can be accessed on the Prop backpack? If any.

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-03-03 03:32
    Short answer: eight (on the daughterboard connector), plus one (serial I/O header), plus two (Prop Plug header).

    -Phil
  • allieallie Posts: 109
    edited 2010-03-07 04:25
    I have a Propeller Backpack coming in the mail which I'm going to interface to my lath and milling machine project through a BS2P40. Will the BS2P40 control the Propeller Backpack with the same code as the BS2. I realize the BS2P40 has more options.
    I want to use the BS2P40 to control my interface board and the Propeller Backpack. The Propeller Backpack can display the info I need to the TV display.
    I also want to interface the BS2P40 to some 74ls logic and I think the 74hct logic chips will do this, am I right.

    Best regards
    Allie
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-03-07 04:31
    allie said...
    Will the BS2P40 control the Propeller Backpack with the same code as the BS2.
    Yes, but you will need to change the baudrate constant to match the speed of the BS2p.

    Regarding your logic chip question, the answer is "yes", but that's really a topic for a new thread.

    -Phil
  • allieallie Posts: 109
    edited 2010-03-07 05:01
    Thanks Phil for your answer, and I'm sorry about the mistake I made in posting the logic chip question. It's been a while since I've been on the forum and I'm a bit rusty.

    Best regards
    Allie
  • logan996logan996 Posts: 281
    edited 2010-03-07 13:41
    this works for a homework board right? even if it has the 220 ohm resistors built in?

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    "When the government is afraid of the people there is liberty, when the people are afraid of the government, there is tryanny"

    · Thomas Jefferson
    ·
  • logan996logan996 Posts: 281
    edited 2010-03-07 13:50
    Also i had an idea! could you buy the blank daughter board and attach a PS/2 connector to it and use a new cog to translate keyboard keys to what they are (like the basic 1-10 and a-z and the other simple special ones) and send that to the BS2 through another 3pin connector? like it would be stored in a varible, well would it even be possible for the propeller to have another cable that way it can send info to the BS2? could it send binary that the BS2 could decode?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "When the government is afraid of the people there is liberty, when the people are afraid of the government, there is tryanny"

    · Thomas Jefferson
    ·
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-03-07 18:32
    logan996 said...
    this works for a homework board right? even if it has the 220 ohm resistors built in?
    Yes.

    Allie,

    Yes, you could do that with a keyboard. You would not even need a separate 3-pin connector for the keyboard input to the Stamp. Your top-level Spin program could be configured to accept and translate commands via the single three-pin connector provided, such that some would be directed to the video and some would poll for keyboard input.

    -Phil
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