Shop OBEX P1 Docs P2 Docs Learn Events
2 LCD displays — Parallax Forums

2 LCD displays

ArchiverArchiver Posts: 46,084
edited 2003-09-05 03:32 in General Discussion
I have two Hitachi Compatible 2 x 16 displays, and a BS2p. I would like to
control both of them. I was thinking of controlling them this way

main:
' for lcd display one

LCDOUT 0, 1 [noparse][[/noparse]"Hello World"]
LCDOUT 0, 64+64 [noparse][[/noparse]"Two displays"]

' for lcd display two
LCDOUT 1, 1 [noparse][[/noparse]"Working"]
LCDOUT 1, 64+64 [noparse][[/noparse]"Together"]
end

This is just a thought. I think it should work. I am paining to connect R/W, RS,
and DB4-DB7 together. Hook E of display one to pin 0, and E of display two to
pin 1. I am trying to use as little of pins as possible.
If anyone thinks this will not work please let me know.

Thanks.
TC

[noparse][[/noparse]Non-text portions of this message have been removed]

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-09-03 03:59
    Yes, this will work -- I've done it. Just remember that you have to
    initialize each before you can start writing to them.

    -- Jon Williams
    -- Applications Engineer, Parallax
    -- Dallas Office


    Original Message
    From: Anthony Conti [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=UALOLoniLG-ynLoEku3hE-4UulDjZe7fOukiPNJo7H4xbLQWO0k0KDGMB_0qnBxuzyVK_b_22VbxZA]aconti@s...[/url
    Sent: Tuesday, September 02, 2003 9:18 PM
    To: basicstamps@yahoogroups.com
    Subject: [noparse][[/noparse]basicstamps] 2 LCD displays


    I have two Hitachi Compatible 2 x 16 displays, and a BS2p. I would like
    to control both of them. I was thinking of controlling them this way

    main:
    ' for lcd display one

    LCDOUT 0, 1 [noparse][[/noparse]"Hello World"]
    LCDOUT 0, 64+64 [noparse][[/noparse]"Two displays"]

    ' for lcd display two
    LCDOUT 1, 1 [noparse][[/noparse]"Working"]
    LCDOUT 1, 64+64 [noparse][[/noparse]"Together"]
    end

    This is just a thought. I think it should work. I am paining to connect
    R/W, RS, and DB4-DB7 together. Hook E of display one to pin 0, and E of
    display two to pin 1. I am trying to use as little of pins as possible.
    If anyone thinks this will not work please let me know.

    Thanks.
    TC

    [noparse][[/noparse]Non-text portions of this message have been removed]


    To UNSUBSCRIBE, just send mail to:
    basicstamps-unsubscribe@yahoogroups.com
    from the same email address that you subscribed. Text in the Subject
    and Body of the message will be ignored.


    Your use of Yahoo! Groups is subject to
    http://docs.yahoo.com/info/terms/




    This message has been scanned by WebShield. Please report SPAM to
    abuse@p....
  • ArchiverArchiver Posts: 46,084
    edited 2003-09-03 04:25
    Haven't tried it with a Stamp, but I have been playing with a 386ex
    single-board computer recently and thats exactly how they do it with two
    displays. All the data lines and control lines are shared by both LCD's
    except the E (enable) line. The LCD's are wired for 4-bit mode.

    Not sure what goes on internally (they have a TSR that outputs DOS
    printer calls to a single 10-pin connector), but I'll bet all they do is
    select one display or the other with the enable line.

    If you want some fun, get a 4x40 display. I found a couple locally at a
    surplus place for $10. Although its a single LCD, the top two lines have
    one complete Hitachi controller, and the bottom two lines have a second
    complete Hitachi controller.

    *****************

    > I have two Hitachi Compatible 2 x 16 displays, and a BS2p. I would like to
    control both of them. I was thinking of controlling them this way
    >
    > main:
    > ' for lcd display one
    >
    > LCDOUT 0, 1 [noparse][[/noparse]"Hello World"]
    > LCDOUT 0, 64+64 [noparse][[/noparse]"Two displays"]
    >
    > ' for lcd display two
    > LCDOUT 1, 1 [noparse][[/noparse]"Working"]
    > LCDOUT 1, 64+64 [noparse][[/noparse]"Together"]
    > end
    >
    > This is just a thought. I think it should work. I am paining to connect R/W,
    RS, and DB4-DB7 together. Hook E of display one to pin 0, and E of display two
    to pin 1. I am trying to use as little of pins as possible.
    > If anyone thinks this will not work please let me know.
  • ArchiverArchiver Posts: 46,084
    edited 2003-09-03 15:41
    -snip-
    > Hook E of display one to pin 0, and E of display two to pin 1. I am trying to
    use as little of pins as possible.
    -snip-
    Perhaps better still, connect E of display 1 to pin 0 and invert pin 0 (a single
    transistor inverter) and feed the inverted pin 0
    signal to the second.
    Make pin 0 high for one display and low for the other.
  • ArchiverArchiver Posts: 46,084
    edited 2003-09-03 15:44
    You should also consider using an I2C compatible LCD such as the Orbital
    Matrix LK202 and simply giving each display a separate network address. And
    it only takes 2 output pins.

    I2COUT 8,$50,[noparse][[/noparse]"Hello World'"]
    I2COUT 8,$51,[noparse][[/noparse]"Hello Mars"]

    would do the trick. The default address is $50, but you can change it to any
    of 127 values. You DO NOT need the memory position bit or submemory position
    bit that are shown in the Stamp Basic syntax.

    Original Message
    From: "Anthony Conti" <aconti@s...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, September 02, 2003 7:18 PM
    Subject: [noparse][[/noparse]basicstamps] 2 LCD displays


    > I have two Hitachi Compatible 2 x 16 displays, and a BS2p. I would like to
    control both of them. I was thinking of controlling them this way
    >
    > main:
    > ' for lcd display one
    >
    > LCDOUT 0, 1 [noparse][[/noparse]"Hello World"]
    > LCDOUT 0, 64+64 [noparse][[/noparse]"Two displays"]
    >
    > ' for lcd display two
    > LCDOUT 1, 1 [noparse][[/noparse]"Working"]
    > LCDOUT 1, 64+64 [noparse][[/noparse]"Together"]
    > end
    >
    > This is just a thought. I think it should work. I am paining to connect
    R/W, RS, and DB4-DB7 together. Hook E of display one to pin 0, and E of
    display two to pin 1. I am trying to use as little of pins as possible.
    > If anyone thinks this will not work please let me know.
    >
    > Thanks.
    > TC
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2003-09-03 17:30
    At 08:41 AM 9/3/2003, FalconWireless Tech Support - KF4HAZ wrote:
    >-snip-
    > > Hook E of display one to pin 0, and E of display two to pin 1. I am
    > trying to use as little of pins as possible.
    >-snip-
    >
    >Perhaps better still, connect E of display 1 to pin 0 and invert pin 0 (a
    >single transistor inverter) and feed the inverted pin 0
    >signal to the second.
    >Make pin 0 high for one display and low for the other.

    That won't work in this case - the 'enable' line is actually the clock
    (latch) line into the display controller. In other words, you have to
    pulse the E line during each transfer. Thus, you will also be pulsing the
    E line into the other unit.

    dwayne

    --
    Dwayne Reid <dwayner@p...>
    Trinity Electronics Systems Ltd Edmonton, AB, CANADA
    (780) 489-3199 voice (780) 487-6397 fax

    Celebrating 19 years of Engineering Innovation (1984 - 2003)
    .-. .-. .-. .-. .-. .-. .-. .-. .-. .-
    `-' `-' `-' `-' `-' `-' `-' `-' `-'
    Do NOT send unsolicited commercial email to this email address.
    This message neither grants consent to receive unsolicited
    commercial email nor is intended to solicit commercial email.
  • ArchiverArchiver Posts: 46,084
    edited 2003-09-04 16:23
    I recently tried using the I2COUT command with the Orbital Matrix LCD available
    through the parallax website. The problem I was having was differentiating
    between sending text and sending LCD commands such as turning the backlight
    on/off. Do you know how to format the data string for text output versus LCD
    control commands?

    Any help would be greatly appreciated.

    MarvL <MarvL@m...> wrote:
    You should also consider using an I2C compatible LCD such as the Orbital
    Matrix LK202 and simply giving each display a separate network address. And
    it only takes 2 output pins.

    I2COUT 8,$50,[noparse][[/noparse]"Hello World'"]
    I2COUT 8,$51,[noparse][[/noparse]"Hello Mars"]

    would do the trick. The default address is $50, but you can change it to any
    of 127 values. You DO NOT need the memory position bit or submemory position
    bit that are shown in the Stamp Basic syntax.

    Original Message
    From: "Anthony Conti"
    To:
    Sent: Tuesday, September 02, 2003 7:18 PM
    Subject: [noparse][[/noparse]basicstamps] 2 LCD displays


    > I have two Hitachi Compatible 2 x 16 displays, and a BS2p. I would like to
    control both of them. I was thinking of controlling them this way
    >
    > main:
    > ' for lcd display one
    >
    > LCDOUT 0, 1 [noparse][[/noparse]"Hello World"]
    > LCDOUT 0, 64+64 [noparse][[/noparse]"Two displays"]
    >
    > ' for lcd display two
    > LCDOUT 1, 1 [noparse][[/noparse]"Working"]
    > LCDOUT 1, 64+64 [noparse][[/noparse]"Together"]
    > end
    >
    > This is just a thought. I think it should work. I am paining to connect
    R/W, RS, and DB4-DB7 together. Hook E of display one to pin 0, and E of
    display two to pin 1. I am trying to use as little of pins as possible.
    > If anyone thinks this will not work please let me know.
    >
    > Thanks.
    > TC
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >



    To UNSUBSCRIBE, just send mail to:
    basicstamps-unsubscribe@yahoogroups.com
    from the same email address that you subscribed. Text in the Subject and Body of
    the message will be ignored.


    Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/



    Do you Yahoo!?
    Yahoo! SiteBuilder - Free, easy-to-use web site design software

    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-09-05 03:32
    On the Orbital Matrix LCD I just toss the command characters right in with
    the text. The 254 is apparently an escape character that alerts the LCD that
    the next (few) characters are command bytes rather than displayable
    character bytes.

    I2COUT 8,$50,[noparse][[/noparse]254,88,"Hello World"] 'Clears the display and writes some
    text

    The only thing I haven't figured out, as yet, is that I still get an extra
    character when I try to define the initial power on default screen.

    Original Message
    From: "Michael Carey" <mrcarey30@y...>
    To: <basicstamps@yahoogroups.com>
    Sent: Thursday, September 04, 2003 8:23 AM
    Subject: Re: [noparse][[/noparse]basicstamps] 2 LCD displays


    > I recently tried using the I2COUT command with the Orbital Matrix LCD
    available through the parallax website. The problem I was having was
    differentiating between sending text and sending LCD commands such as
    turning the backlight on/off. Do you know how to format the data string for
    text output versus LCD control commands?
    >
    > Any help would be greatly appreciated.
    >
    > MarvL <MarvL@m...> wrote:
    > You should also consider using an I2C compatible LCD such as the Orbital
    > Matrix LK202 and simply giving each display a separate network address.
    And
    > it only takes 2 output pins.
    >
    > I2COUT 8,$50,[noparse][[/noparse]"Hello World'"]
    > I2COUT 8,$51,[noparse][[/noparse]"Hello Mars"]
    >
    > would do the trick. The default address is $50, but you can change it to
    any
    > of 127 values. You DO NOT need the memory position bit or submemory
    position
    > bit that are shown in the Stamp Basic syntax.
    >
    >
    Original Message
    > From: "Anthony Conti"
    > To:
    > Sent: Tuesday, September 02, 2003 7:18 PM
    > Subject: [noparse][[/noparse]basicstamps] 2 LCD displays
    >
    >
    > > I have two Hitachi Compatible 2 x 16 displays, and a BS2p. I would like
    to
    > control both of them. I was thinking of controlling them this way
    > >
    > > main:
    > > ' for lcd display one
    > >
    > > LCDOUT 0, 1 [noparse][[/noparse]"Hello World"]
    > > LCDOUT 0, 64+64 [noparse][[/noparse]"Two displays"]
    > >
    > > ' for lcd display two
    > > LCDOUT 1, 1 [noparse][[/noparse]"Working"]
    > > LCDOUT 1, 64+64 [noparse][[/noparse]"Together"]
    > > end
    > >
    > > This is just a thought. I think it should work. I am paining to connect
    > R/W, RS, and DB4-DB7 together. Hook E of display one to pin 0, and E of
    > display two to pin 1. I am trying to use as little of pins as possible.
    > > If anyone thinks this will not work please let me know.
    > >
    > > Thanks.
    > > TC
    > >
    > > [noparse][[/noparse]Non-text portions of this message have been removed]
    > >
    > >
    > > To UNSUBSCRIBE, just send mail to:
    > > basicstamps-unsubscribe@yahoogroups.com
    > > from the same email address that you subscribed. Text in the Subject and
    > Body of the message will be ignored.
    > >
    > >
    > > Your use of Yahoo! Groups is subject to
    http://docs.yahoo.com/info/terms/
    > >
    > >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
    >
    > Do you Yahoo!?
    > Yahoo! SiteBuilder - Free, easy-to-use web site design software
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
Sign In or Register to comment.