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Propellor USB Prop Plug and serial communication newbie question — Parallax Forums

Propellor USB Prop Plug and serial communication newbie question

whiteoxewhiteoxe Posts: 794
edited 2009-09-18 22:21 in Propeller 1
My propellor should be arriving any time now smilewinkgrin.gif and I'm excited! I wanted to get the PE Education Kit but it was sold out, no matter, Ill get by!

My question is pretty basic, does the prop plug behave like a serial com port ? I will be writing a Visual Basic program to commiunicate with the Propellor and the only way I know how how to do this with any chip is using serial ports.

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2009-09-17 22:33
    Yes, it can operate both as a programming port and as a serial communication port.

    -Phil
  • StefanL38StefanL38 Posts: 2,292
    edited 2009-09-17 22:38
    Hello Whiteoxe,

    Yes the prop-plug has an FTDI-chip that does the conversion from USB to serial creating a virtual COM-Port.
    Make sure you have installed the newest driver for the FTDI-Chip

    There is one thing to know. Most Applications toggle the DTR-line when opening the COM-Port this creates a reset on the propeller.
    Whenever the propeller resets the content of the RAM gets lost and overwritten by the content of the EEPROM.
    So when working with the serial connection on PIN 31,30 it's better to store EVERY new program-version in the EEPROM
    because in RAM it will be lost after opening the COM-Port. An Exception to this rule is the PST.EXE (Parallax Serial Terminal)

    it does NOT automatically toggle the DTR-Line

    best regards

    Stefan
  • Mike GreenMike Green Posts: 23,101
    edited 2009-09-17 22:38
    Yes, the PropPlug behaves like a serial port. The only "odd" thing about the programming port on the Propeller is that the DTR signal causes a Propeller reset when it's toggled (deliberately). Be sure to write your PC program so it doesn't change DTR when the serial port is opened or closed and you'll be fine.

    Download "DongleBasic" from the Propeller Object Exchange. It's a Basic subset interpreter that uses a minimal Propeller and just needs the programming comm port and a terminal program (like Hyperterm) on the PC for a console. It'll let you experiment with the Propeller's I/O pins and the built-in counters among other things.
  • whiteoxewhiteoxe Posts: 794
    edited 2009-09-18 02:28
    Thanks for your replies. I can get by i think without knowing what is DTR, but in anycase what is that ?

    Mike.L.
  • KyeKye Posts: 2,200
    edited 2009-09-18 02:56
    Data Terminal Ready. The line tells the modem when the computer is ready to send data. The modem in this case is your prop chip. And the line is used to reset the device so that the boorloader can communicate to the pc.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Nyamekye,
  • whiteoxewhiteoxe Posts: 794
    edited 2009-09-18 22:21
    Just a note; I changed my name from thewhiteoxe to greenspinner, as Im new to spin and never did like my username [noparse]:)[/noparse]
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