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Connection Cable

ArchiverArchiver Posts: 46,084
edited 2004-04-28 14:49 in General Discussion
Hey Again Everyone
It's me again!
I still havn't gotten it to work and i'm fed up. Just about to throw
it out the window in frustration. If you don't know what i'm talking
about just read my prior posts entitled, "Programming Board
Trouble". Anyways one quick question. Are the SerIn and SerOut and
DTR and GND pins from the stamp supposed to get power from the stamp
directly? Or do they get power from the serial port? because when i
try to test the connections with my multimeter i only get readings
when the stamp is connected to the pc and it has power from the nine
volt battery. But even if the stamp is powered, if i don't have it
connected to the pc, I don't get any readings from those pins.
Please advise!
Thx again for putting up with me!
Jason Chechik

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-04-28 14:43
    The BS2 has a very clever way of using the
    PC serial port RS-232 voltage, so the BS2
    does not need a 12-volt regulator on chip.

    It uses a few transistors, which are driven
    from the PC 'TX' (SERIN) signal. So you are
    correct, they are not driven from the BS2.

    The BS2 'TX' line (SEROUT) uses the PC's
    'TX' signal's 12 volts. It switches that
    voltage to make the signal the BS2 sends
    back to the PC.

    When I first saw this, I thought it was a
    little radical -- but it works VERY well.
    I put it in the category of being a
    "Clever Hack".

    --- In basicstamps@yahoogroups.com, "Jason Chechik"
    <one_ied_freakazoid@h...> wrote:
    > Hey Again Everyone
    > It's me again!
    > I still havn't gotten it to work and i'm fed up. Just about to
    throw
    > it out the window in frustration. If you don't know what i'm
    talking
    > about just read my prior posts entitled, "Programming Board
    > Trouble". Anyways one quick question. Are the SerIn and SerOut and
    > DTR and GND pins from the stamp supposed to get power from the
    stamp
    > directly? Or do they get power from the serial port? because when i
    > try to test the connections with my multimeter i only get readings
    > when the stamp is connected to the pc and it has power from the
    nine
    > volt battery. But even if the stamp is powered, if i don't have it
    > connected to the pc, I don't get any readings from those pins.
    > Please advise!
    > Thx again for putting up with me!
    > Jason Chechik
  • ArchiverArchiver Posts: 46,084
    edited 2004-04-28 14:49
    Try this

    <http://www.qsl.net/kf4haz/cables/stamps/>

    KF4HAZ - Lonnie
    From: "Jason Chechik" <one_ied_freakazoid@h

    > Hey Again Everyone
    > It's me again!
    > I still havn't gotten it to work and i'm fed up. Just about to throw
    > it out the window in frustration. If you don't know what i'm talking
    > about just read my prior posts entitled, "Programming Board
    > Trouble". Anyways one quick question. Are the SerIn and SerOut and
    > DTR and GND pins from the stamp supposed to get power from the stamp
    > directly? Or do they get power from the serial port? because when i
    > try to test the connections with my multimeter i only get readings
    > when the stamp is connected to the pc and it has power from the nine
    > volt battery. But even if the stamp is powered, if i don't have it
    > connected to the pc, I don't get any readings from those pins.
    > Please advise!
    > Thx again for putting up with me!
    > Jason Chechik
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