"hello world" with 18f6680


Closed Thread
Results 1 to 40 of 92

Hybrid View

  1. #1
    skimask's Avatar
    skimask Guest


    Did you find this post helpful? Yes | No

    Default

    Quote Originally Posted by dragons_fire View Post
    OSC1-OSC2, it shows 0V
    OSC1-GND, it shows 2.5V
    OSC2-GND, it shouws 3.6V
    OSC1-2 - should show more than that, but your meter probably won't respond quick enough. Got an AC setting you can try?

    OSC1/2 - GND - both sound good to me.

    In your schematic, is that a 20Mhz resonator, crystal?
    Try changing your config's to use a different type of clock, R/C, external, whatever, see what happens.

  2. #2
    Join Date
    Apr 2006
    Location
    Alberta Canada
    Posts
    166


    Did you find this post helpful? Yes | No

    Default

    i tried checking voltage again. i get around 3mV DC across OSC1-OSC2. on the AC setting it shows nothing but im using a digital meter which might be too slow. i dug out my analog meter, but i have no clue where the leads are for it....

    the OSC is a 20.0Mhz ceramic resonator with built in caps. its mountet fairly close to the PIC.

    i have tried some of the different clock settings with no luck and i have switched resonators once just in case it was a bad one...

  3. #3
    skimask's Avatar
    skimask Guest


    Did you find this post helpful? Yes | No

    Default

    Quote Originally Posted by dragons_fire View Post
    i get around 3mV DC across OSC1-OSC2
    That sounds a bit goofy, but I'm not looking at what you're dealing with.

    Have you tried a SLOWER oscillator yet, like the R/C, anything, just a signal enough to get it moving?
    Heck anything, clicking a push button on/off on the OSC1 pin?

    And give these config settings a shot:

    OSC "HS" - good

    System clock "disabled" - good enough, but I like to leave it enabled so I can play with
    changing clock speeds

    power up timer "disabled" - I'd enable it, gives the clocks more time to spool up and stabilize, causes fewer errors, especially at higher speeds

    brown out reset "enabled" - ok, if you're into that sort of thing

    brown out voltage "2.0V" - good

    watchdog timer " enabled" - don't need it, so disable it

    the rest are good...in my mind anyways...

  4. #4
    Join Date
    Nov 2003
    Location
    Wellton, U.S.A.
    Posts
    5,924


    Did you find this post helpful? Yes | No

    Default

    Are you setting the fuses in the code or in the *.inc?

    Either way, Post what you have, I know what you say you have but how? The 18s sometimes are a bit "picky" this way. At least with different versions of PBP.
    Dave
    Always wear safety glasses while programming.

  5. #5
    Join Date
    Apr 2006
    Location
    Alberta Canada
    Posts
    166


    Did you find this post helpful? Yes | No

    Default

    there in the inc file.. i was just reading them from the epic programmer. it has a list of what everything is set as, and i can change it there too..

    i made it all with SMT stuff, and its pretty tiny (yes ive checked for crossed traces) so i have no other OSC's to connect to it. and i think its too small to wire up jumpers too...

  6. #6
    Join Date
    Apr 2006
    Location
    Alberta Canada
    Posts
    166


    Did you find this post helpful? Yes | No

    Default

    heres my INC file..


    NOLIST
    ifdef PM_USED
    LIST
    "Error: PM does not support this device. Use MPASM."
    NOLIST
    else
    LIST
    LIST p = 18F6680, r = dec, w = -311,w = -230, f = inhx32
    INCLUDE "P18F6680.INC" ; MPASM Header
    __CONFIG _CONFIG1H, _OSC_HS_1H
    __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
    __CONFIG _CONFIG4L, _LVP_OFF_4L
    NOLIST
    endif
    LIST
    EEPROM_START EQU 0F00000h
    BLOCK_SIZE EQU 8

  7. #7
    Join Date
    Nov 2003
    Location
    Wellton, U.S.A.
    Posts
    5,924


    Did you find this post helpful? Yes | No

    Default

    See post 14 of this thread. One of the PBP versions fixed this but I am not sure which one, Been doing it this way since 2.43. Still works for me.
    Dave
    Always wear safety glasses while programming.

Similar Threads

  1. 18f6680 N/C
    By mackrackit in forum Off Topic
    Replies: 2
    Last Post: - 29th April 2008, 20:21
  2. need help with "hello world" in hyperterm
    By ericmiles in forum Serial
    Replies: 3
    Last Post: - 31st October 2007, 15:08
  3. 18F6680 and portd problems.
    By jkbh in forum mel PIC BASIC Pro
    Replies: 10
    Last Post: - 6th June 2005, 10:54

Members who have read this thread : 0

You do not have permission to view the list of names.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts