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Programmer questions

stlericstleric Posts: 13
edited 2012-12-10 11:56 in BASIC Stamp
In the BS2 docs, where the programmer hookup is diagrammed, the DSR and RTS pins are jumpered together at the PC side connector. Is this connection necessary? Is this something that's required by the BASIC Stamp Editor?

Second question: I have a Parallax USB to serial adapter, with cable (Parallax P/N 28031-RT. Is there a diagram of the DB9 pinout somewhere? I'm not 100% but it seems that pins 2 and 3 are swapped wrt what's on my PC's COM port.

TIA
eric

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2012-12-08 20:48
    1) DSR and RTS need not be jumpered although the Stamp Editor will warn you that they're not connected. If DSR and RTS are intact, the serial cable is likely to be plugged in ... a simple check.
    2) Not sure what you're looking for. The diagram on page 28 of the BASIC Stamp Syntax and Reference Manual shows the 4 pins needed for programming (Rx, TX, DTR, Gnd) plus DSR and RTS as noted above.
  • stlericstleric Posts: 13
    edited 2012-12-09 09:49
    Mike Green wrote: »
    2) Not sure what you're looking for. The diagram on page 28 of the BASIC Stamp Syntax and Reference Manual shows the 4 pins needed for programming (Rx, TX, DTR, Gnd) plus DSR and RTS as noted above.

    As I said, I'm looking for the pinout of the DB9 side of the 28031. Does the 28031 utilize all signals (DSR, DTR, RTS, CTS, etc)? And in particular, which pin is RX and which is TX (as I said originally, it seems as if the RX and TX pins are flipped relative to what's on my computer's COM port).

    Regards,
    eric
  • Tracy AllenTracy Allen Posts: 6,664
    edited 2012-12-10 08:10
    The DB9 connections to the Stamp carriers are,
    5 - common
    4 - DTR, ATN input to Stamp, active high reset
    3 - TX, data input to Stamp
    4 - RX, data output from Stamp

    6 - DSR is wired to
    7 - RTS output from PC (this is special ID for the Parallax cable)

    The DB9 on the Stamp carrier boards is wired DCE, and the PC side is normally wired DTE. So the cable is straight through from pin 2 to pin 2 and from pin 3 to pin 3. The signal names are with respect to the PC DTE side, that is, TX is an output from the PC and an input to the Stamp.
  • Tracy AllenTracy Allen Posts: 6,664
    edited 2012-12-10 08:23
    I should add that the #28031adapter itself is a full implementation of the DB9 signals. All 9 pins are implemented and it is wired as if you had a straight-thru cable going to a real DB9 serial port.

    The DSR-RTS connection is made on the Stamp carrier board, not on the #28031, nor on the Stamp module itself.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2012-12-10 10:28
    stleric wrote: »
    I have a Parallax USB to serial adapter, with cable (Parallax P/N 28031-RT. Is there a diagram of the DB9 pinout somewhere? I'm not 100% but it seems that pins 2 and 3 are swapped wrt what's on my PC's COM port.

    eric

    I'm curious why you think the pins are swapped?
  • stlericstleric Posts: 13
    edited 2012-12-10 11:50
    Tracy Allen wrote: »
    I should add that the #28031adapter itself is a full implementation of the DB9 signals. All 9 pins are implemented and it is wired as if you had a straight-thru cable going to a real DB9 serial port.

    The DSR-RTS connection is made on the Stamp carrier board, not on the #28031, nor on the Stamp module itself.

    This is what I was looking for, thanks.

    eric
  • stlericstleric Posts: 13
    edited 2012-12-10 11:56
    Chris Savage wrote: »
    I'm curious why you think the pins are swapped?

    Kind of a long story and probably moot as everything now seems to be behaving like I'd expect.

    eric
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