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Parallax LCD Help — Parallax Forums

Parallax LCD Help

John.GrayJohn.Gray Posts: 22
edited 2006-05-08 20:50 in General Discussion
· I am using the BasicMicro 08/18 development board to connect to a Parallax serial LCD, model 27979.· I am having problems.· I am using the 16F628.

CPU = 16F628
MHZ = 10
CONFIG 16142
·
·
·
DISP CON B0
DISP_BAUD CON i19200· 'invert data at baud of 19200
·
·
SEROUT DISP,DISP_BAUD,[noparse][[/noparse]"TEST"]

has anyone here had problems like this or did I miss something?

Comments

  • ForrestForrest Posts: 1,341
    edited 2006-04-15 13:56
    I'm no expert on the Parallax serial LCD, but after glancing at the Stamp in Class LCD tutorial I've determined you must send a command to initialize the LCD first AND you must wait until the initialization command finishes (PAUSE command) before sending data to the LCD.

    The Stamps in Class LCD link is at the bottom of this page
    www.parallax.com/detail.asp?product_id=27979
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2006-04-15 14:41
    The Stamps in Class stuff is for Parallel LCDs.· John.Gray has stated that he's trying to use a Serial LCD.· I don't know what this "BasicMicro 08/18 development board" is.· Is that a Parallax product, something for the SX?
  • ForrestForrest Posts: 1,341
    edited 2006-04-15 14:53
    PJ Allen,
    Your information is outdated - the new Stamps in Class tutorial I linked to is for the Parallax serial LCD. The examples are in PBasic - and will need to converted to MBasic before you can run them on a PIC processor.
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2006-04-15 14:53
    The Parallax serial LCD uses True data mode, not Inverted -- a simple change to your baud constant should fix everything.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Jon Williams
    Applications Engineer, Parallax
  • John.GrayJohn.Gray Posts: 22
    edited 2006-04-15 17:01
    The BASIC MICRO is supposed to be 99% STAMP compatiable...the Jury is still out on that, as far as sending data, I did a HIGH B0 in this case and did various pauses....50 up til 1000. the command modifer for SEROUT in MBASIC is either N for not invert or I for invert, I went from 2400 up to 19200 using both N and I as the modifer, if I use say

    DISP CON B0

    DISP_BAUD CON n19200 ' data at baud of 19200

    SEROUT DISP,DISP_BAUD,[noparse][[/noparse]"TEST"]

    then the LCD shows ?>>>?>>
    when I invert it shows TEST, that's why I have been inverting the data...right, wrong or otherwise, I'm still cracking the code using this MBASIC and a PIC 16F628...I should have just went from PBASIC to Assembly to begin with. Anyway, what I'm thinking about doing now is using the BS2 to control the LCD and Keypad with MEMKEY and seperate the target and use the PIC 16F628 for the I/O commands (The reason behind NOT using the STAMP is $$$$, the PIC 16F628 runs for under $3.00 a pop and the life cycle of the target we deal with is less that 30 minutes before it gets destroyed. That being said, now I'm thinking trying to get the STAMP to communicate with the 16F628 might be a whole new can of worms. The LCD and keypad will be detachable so the operator can select the variables in the program and we don't replace 15 STAMPS a day.
  • Jon WilliamsJon Williams Posts: 6,491
    edited 2006-04-15 17:32
    Do you have both DIP switches set to ON for 19.2K? I've used our serial LCD with BASIC Stamp, Javelin Stamp, the SX, and am currently using it as an output with our Propeller chip -- I'm pretty sure it works and the issue is with the B/M compiler. What that issue is... I couldn't tell you; you'll need to consult with them.

    They may have a different definition of inverted data; we consider inverted data when the start bit = 1, true data has the start bit = 0. So, just figure out which works with their compiler and the rest of it should be easy. The Parallax Serial LCD behaves like a simpler terminal; once you can write something, you can do anything. Once you understand who their serial stuff works, you should be able to communicate with the Stamp fairly easily, you can even using our SERIN/SEROUT examples.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Jon Williams
    Applications Engineer, Parallax
  • ForrestForrest Posts: 1,341
    edited 2006-04-15 21:44
    The SX28 is $3.49 each and example code SX/B (Basic) code is available at my original link. www.parallax.com/detail.asp?product_id=SX28AC/DP
  • John.GrayJohn.Gray Posts: 22
    edited 2006-05-08 20:50
    · I biggest reason for not using the SX28 was it is 28 pins, alot of the things we do we need to use a 8 or 18 pin PIC, but fear not, I did order the SX28 and am trying to learn how to use it for when we need the I/O that it offers
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