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  1. #1
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    What's your hardware setup? Got a picture? Can you show the whole code? I wonder what your TX pin is doing with the serial in, but I can't tell from here.

    The code you just posted is not inverted, so I assume you have the max232 back in?
    http://www.scalerobotics.com

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    Quote Originally Posted by scalerobotics View Post
    What's your hardware setup? Got a picture? Can you show the whole code? I wonder what your TX pin is doing with the serial in, but I can't tell from here.

    The code you just posted is not inverted, so I assume you have the max232 back in?
    hi

    my brother has my cam at the moment, i will get it off of him tomorrow.

    quick question - i'm using a 16F870 will it accept voltages as low as 3.3v on an I/O pin

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    What does C.0 do? does it flash an LED?

    if its used for something else, then it might be a good idea to ad an LED and make it flash on and off as your program runs. I find that it helps me know where the program is getting hung up or if its running at all..

    One other thing, and im not sure if its right or not, but wheni use an external osc i need to set it to HS not XT.

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    Quote Originally Posted by dragons_fire View Post
    What does C.0 do? does it flash an LED?

    if its used for something else, then it might be a good idea to ad an LED and make it flash on and off as your program runs. I find that it helps me know where the program is getting hung up or if its running at all..

    One other thing, and im not sure if its right or not, but wheni use an external osc i need to set it to HS not XT.

    hi yes portc.0 is used to flash an led, so i know its recieving serial data.

    the pic micro it self is running as it output's a test message to the pc's serial port and that is sent fine

  5. #5
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    Also

    i measured the voltage on the pin which transmits the serial data fron the gps module, and it was only 1.5v, now is that normal.

    the pic micro will not see the data at such low levels will it ?
    Last edited by rondo2; - 30th June 2009 at 20:38.

  6. #6
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    Quote Originally Posted by rondo2 View Post
    i'm using a 16F870 will it accept voltages as low as 3.3v on an I/O pin
    Data Sheet: "Wide operating range 2.0 to 5.5v . . . " I would make my own headaches small and run the
    pic and gps on 3.3v, 1 supply 1 headache 2 supplies 2 . . .

    Quote Originally Posted by rondo2 View Post
    Also

    i measured the voltage on the pin which transmits the serial data fron the gps module, and it was only 1.5v, now is that normal.

    the pic micro will not see the data at such low levels will it ?
    3 ways to get fish, buy fish, learn to fish, beg fish at the dock ... to learn to fish you have to observe others
    even if their fishing is not what you want today. I mean by this, read posts that do not apply to what you are doing today <br>
    Look at the GPS data sheet, it's pretty thin I admit. Your GPS unit communicates @ 9600 b True, which means it is
    "active low" as stated in the data sheet. This means it does not supply +5 or +3.3 on that port. Where does it get it? From the
    pullup resistor, you are going to put on that line to the 3.3v supply. True requires a pullup whereas Inverted
    would like to idle low with a pulldown.

    Quote Originally Posted by rondo2 View Post
    hi thanks for pointing that out but still nothing.

    i changed my code to serin2 TX,<font color = red>84</font color>,[WAIT("$GPGGA"),WAIT(","),DEC2 H,DEC2 M,DEC2 S]


    PAUSE 200

    HIGH PORTC.0
    PAUSE 200
    LOW PORTC.0
    PAUSE 200

    SEROUT2 PORTC.1,16468,[dec2 H, dec2 M, dec2 S]

    GOTO MAIN
    84 sets serin2 to Driven true 32852 sets it to open true. Try the open true setting
    Code:
    @ device  pic16f870,BOD_on
    turn this OFF until everything else works and turn on PWRTE ON, it just gives the power supply a little time to stabalise before the PIC boots
    Code:
    @ device  pic16f870,XT_OSC             'Using External Oscillator
    I honestly do not if this will cause problems given your 20 mhz define, since you are using an external OSC, but why chance it ?
    I would make it HS, might not change anything, except you will know for sure that is NOT a problem.
    Last edited by Archangel; - 30th June 2009 at 23:05.
    If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets.
    .
    Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves
    .
    There simply is no "Happy Spam" If you do it you will disappear from this forum.

  7. #7
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    Quote Originally Posted by Joe S. View Post
    Data Sheet: "Wide operating range 2.0 to 5.5v . . . " I would make my own headaches small and run the
    pic and gps on 3.3v, 1 supply 1 headache 2 supplies 2 . . .



    3 ways to get fish, buy fish, learn to fish, beg fish at the dock ... to learn to fish you have to observe others
    even if their fishing is not what you want today. I mean by this, read posts that do not apply to what you are doing today <br>
    Look at the GPS data sheet, it's pretty thin I admit. Your GPS unit communicates @ 9600 b True, which means it is
    "active low" as stated in the data sheet. This means it does not supply +5 or +3.3 on that port. Where does it get it? From the
    pullup resistor, you are going to put on that line to the 3.3v supply. True requires a pullup whereas Inverted
    would like to idle low with a pulldown.


    84 sets serin2 to Driven true 32852 sets it to open true. Try the open true setting
    Code:
    @ device  pic16f870,BOD_on
    turn this OFF until everything else works and turn on PWRTE ON, it just gives the power supply a little time to stabalise before the PIC boots
    Code:
    @ device  pic16f870,XT_OSC             'Using External Oscillator
    I honestly do not if this will cause problems given your 20 mhz define, since you are using an external OSC, but why chance it ?
    I would make it HS, might not change anything, except you will know for sure that is NOT a problem.
    HI Joe,

    the open true serial settings fixed it

    thanks a lot

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