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Polaroid 6500

ArchiverArchiver Posts: 46,084
edited 2000-11-08 11:18 in General Discussion
At 11/7/2000 03:23 PM, you wrote:
>I'm hoping somebody in stamp land out there can help me with a slight
>problem, using the following programme
>
>TIMEOFFLIGHT var word
>DISTANCE var word
>ECHO con 15
>INIT con 14
>SETTLETIME con 1
>CYCLEDELAY con 300
>
>loop:
>
>high INIT
> 'see the 6500 app notes for timing info
>pause SETTLETIME
>
>rctime ECHO,0,TIMEOFFLIGHT
> 'waits for ECHO to go low,
> 'which signals a return ping.
> 'thereshold is 1.4 volts.
>gosub ECHORECEIVED
>
>low INIT
>
>pause CYCLE_DELAY (this line would not work so changed for CYCLEDELAY)
>
>goto loop
>
>,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
>
>ECHORECEIVED:
>
>DISTANCE = TIMEOFFLIGHT *7/200+22
> 'this conversion approximates centimetres,
> 'accounting for the offset imposed by the
> 'blanking signal generated by the 6500
>debug dec? DISTANCE
> 'print distance on screen
>return
>
>(typed out exactly as given on the
><mailto:nathans@i...>nathans@i..., except
>the bits in brackets)
>

Check here: [noparse]/noparse] [url=http://www.hobbyrobot.com/sensors/6500faq.html]http://www.hobbyrobot.com/sensors/6500faq.html[/url
and then look at App Note #4 [noparse][[/noparse] 6500-BS2.pdf ] on the web site.
That is a copy of the Nahans document.

Make SURE you see this:

"Code Listing Correction: INIT CON should be 9 not 14 and ECHO CON should
be 10 not 15."

Hope that straightens it out.

regards,

Bruce Bates

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2000-11-07 15:23
    I'm hoping somebody in stamp land out there can help me with a slight problem, using the following programme

    TIMEOFFLIGHT var word
    DISTANCE var word
    ECHO con 15
    INIT con 14
    SETTLETIME con 1
    CYCLEDELAY con 300

    loop:

    high INIT
    ··· 'see the 6500 app notes for timing info
    pause SETTLETIME

    rctime ECHO,0,TIMEOFFLIGHT
    ··· 'waits for ECHO to go low,
    ··· 'which signals a return ping.
    ··· 'thereshold is 1.4 volts.
    gosub ECHORECEIVED

    low INIT

    pause CYCLE_DELAY······ (this line would not work so changed for CYCLEDELAY)

    goto loop

    ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

    ECHORECEIVED:

    DISTANCE = TIMEOFFLIGHT *7/200+22
    ··· 'this conversion approximates centimetres,
    ··· 'accounting for the offset imposed by the
    ··· 'blanking signal generated by the 6500
    debug dec? DISTANCE
    ··· 'print distance on screen
    return

    (typed out exactly as given on the nathans@ieland.stanford.edu, except the bits in brackets)

    the problem i'm getting is that, the debug screen displays 'distance=22' no matter what distance I set the sensor at. I have the 4k7 pull up resistor and the 470uf capacitor in place. The line that includes *7/200+22 if I change the 22 for any other number the debug displays that instead. If anybody has experienced similar problems with the 6500 board or any other problems please let me know. And if anybody knows how to fix them then I especially want to hear from you.
    Many thanks in advance.
    John
  • ArchiverArchiver Posts: 46,084
    edited 2000-11-08 11:18

    Original Message
    From: john & lisa
    To: basicstamps@egroups.com
    Sent: Tuesday, November 07, 2000 3:23 PM
    Subject: Polaroid 6500

    I'm hoping somebody in stamp land out there can help me with a slight problem, using the following programme

    TIMEOFFLIGHT var word
    DISTANCE var word
    ECHO con 15
    INIT con 14
    SETTLETIME con 1
    CYCLEDELAY con 300

    loop:

    high INIT
    ··· 'see the 6500 app notes for timing info
    pause SETTLETIME

    rctime ECHO,0,TIMEOFFLIGHT
    ··· 'waits for ECHO to go low,
    ··· 'which signals a return ping.
    ··· 'thereshold is 1.4 volts.
    gosub ECHORECEIVED

    low INIT

    pause CYCLE_DELAY······ (this line would not work so changed for CYCLEDELAY)

    goto loop

    ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

    ECHORECEIVED:

    DISTANCE = TIMEOFFLIGHT *7/200+22
    ··· 'this conversion approximates centimetres,
    ··· 'accounting for the offset imposed by the
    ··· 'blanking signal generated by the 6500
    debug dec? DISTANCE
    ··· 'print distance on screen
    return

    (typed out exactly as given on the nathans@ieland.stanford.edu, except the bits in brackets)

    the problem i'm getting is that, the debug screen displays 'distance=22'· and/or diffrent other numbers normally 3 numbers i.e 'distance=147' no matter what distance I set the sensor at. These numbers are totaly random so making programing very difficult. I have the 4k7 pull up resistor and the 470uf capacitor in place. The line that includes *7/200+22 if I change the 22 for any other number the debug displays that instead. If anybody has experienced similar problems with the 6500 board or any other problems please let me know. And if anybody knows how to fix them then I especially want to hear from you.
    Many thanks in advance.
    John
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