Shop OBEX P1 Docs P2 Docs Learn Events
Serial question about DEBUG and using SERIN on port 16 BS2P — Parallax Forums

Serial question about DEBUG and using SERIN on port 16 BS2P

ArchiverArchiver Posts: 46,084
edited 2003-05-20 21:38 in General Discussion
I have some code that worked on port pin 0 and 1 but I decided to use the
DEBUG port to cut down on parts and pin requirements. Debug sends my data
out as expected but when I use SERIN with a pin argument of 16 I get a
strange artifact. The serial port echos each character back as it comes in.
I assume there is no way around this short of modifying the stamp hardware.
Is that loopback required for the programming function?

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2003-05-20 21:36
    You're right, you cannot avoid the character echo when you send data to the
    Stamp's programming port. It's not too tough to work around this by having
    your external app filter the echo.

    -- Jon Williams
    -- Parallax

    In a message dated 5/20/2003 2:09:52 PM Central Standard Time,
    larrysr@m... writes:

    > I have some code that worked on port pin 0 and 1 but I decided to use the
    > DEBUG port to cut down on parts and pin requirements. Debug sends my data
    > out as expected but when I use SERIN with a pin argument of 16 I get a
    > strange artifact. The serial port echos each character back as it comes in.
    > I assume there is no way around this short of modifying the stamp hardware.
    > Is that loopback required for the programming function?



    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2003-05-20 21:38
    No, it's an artifact of the way they do the 232 driver
    on the BS2. They use the Tx-In signal voltage to
    drive the Rx-Out signal. And no, there's no way
    to defeat it (this from earlier Parallax people's
    posts).

    Ignoring the echo has been the recommendation.

    --- In basicstamps@yahoogroups.com, "Larry G. Nelson Sr"
    <larrysr@m...> wrote:
    > I have some code that worked on port pin 0 and 1 but I decided to
    use the
    > DEBUG port to cut down on parts and pin requirements. Debug sends
    my data
    > out as expected but when I use SERIN with a pin argument of 16 I
    get a
    > strange artifact. The serial port echos each character back as it
    comes in.
    > I assume there is no way around this short of modifying the stamp
    hardware.
    > Is that loopback required for the programming function?
Sign In or Register to comment.