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Can't connect to Propeller — Parallax Forums

Can't connect to Propeller

Mercury1964Mercury1964 Posts: 15
edited 2014-06-06 12:01 in Propeller 1
I apologize if this is in the wrong subforum.

I decided to use the Propeller in an embedded project of mine. After buying the DIP version and assembling a little test circuit on a breadboard, I found that I couldn't get any computer-side loaders to communicate with the Propeller. So far, I've tried:
  • Triple-checking the circuit (built from this diagram)
  • Two different serial adapters (both working, I used them to fix my NAS last week)
  • Adding myself to the "dialout" group and rebooting
  • Giving "/dev/ttyUSB0" full user permissions
and used:
  • BST and SimpleIDE under Ubuntu 14.04
  • PropTool under Windows 7 in Virtualbox (same computer)
  • PropTool on a real Windows 7 machine
All report that there was no Propeller on the selected serial port, and BST further states "Timeout failed at read 1". I'm at a bit of a loss as to what to do now, has anyone else had this problem?

Comments

  • T ChapT Chap Posts: 4,223
    edited 2014-06-05 05:21
    Hello, if you are using a USB interface with the FT232 variant, have you put on the FTDI USB driver? Although I think if you run the Proptool installer it puts on the FTDI drivers automatically. When you plug in the USB device, does your PC make a sound with a notice that a device was found?
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 06:53
    Yes, I installed the drivers for the FTDI on both Windows machines.
  • T ChapT Chap Posts: 4,223
    edited 2014-06-05 07:06
    I spent hours one time with a problem to find out a new USB cable was bad. Verify with a meter that you have 3v3 at VDD plus GND at VSS. A photo of the setup may help.
  • PublisonPublison Posts: 12,366
    edited 2014-06-05 07:17
    Are you using the PropPlug. Some third party USB adapters do not work.

    Could you include a picture of your setup? Sometime the power rails on breadboards are split in the middle, and you have to provide a jumper to power the entire rail. I don't know how many times that bit me.

    EDIT: T Chap posted the pic question as I was typing.
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 07:35
    I'm not using a PropPlug (I'm broke :lol:). I did confirm I'm getting 3.3V and GND on the Propeller's power pins. I'm away from it right now, but I can post a picture when I get home
  • PublisonPublison Posts: 12,366
    edited 2014-06-05 07:49
    Which USB adapter are you using? I think that's your problem. Some adapters do not produce the correct DTR signal.
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 08:03
    I'm using this one, as it's the only one I have with a reset line at all. It's cheaply made, but it's a Silicon Labs UART and puts out the correct voltages
  • jazzedjazzed Posts: 11,803
    edited 2014-06-05 08:13
    Mercury1964 wrote: »
    I'm using this one, as it's the only one I have with a reset line at all. It's cheaply made, but it's a Silicon Labs UART and puts out the correct voltages
    In SimpleIDE, change the Menu -> Tools -> Properties -> General tab -> Reset Signal to RTS.
  • PublisonPublison Posts: 12,366
    edited 2014-06-05 08:15
    Mercury1964 wrote: »
    I'm using this one, as it's the only one I have with a reset line at all. It's cheaply made, but it's a Silicon Labs UART and puts out the correct voltages

    Then the FTDI drivers will have no effect on that device. Have you downloaded the drivers from Silicon Labs?
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 08:26
    Have you downloaded the drivers from Silicon Labs?

    Yes. I apologize, that's what I meant earlier.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-06-05 08:31
    jazzed wrote: »
    In SimpleIDE, change the Menu -> Tools -> Properties -> General tab -> Reset Signal to RTS.

    Most (all?) of the Propeller loading tool default to using the DTR line to toggle the reset. Many USB to serial devices use the RTS line to reset microcontrollers. As jazzed suggests, you will likely need to change this setting in the program software you're using. Jazzed showed you how to find the setting in SimpleIDE, if you need help finding this setting in the other tools let us know and we can help you find where to change the setting.
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 09:07
    Thanks everyone! I'll try that when I get home and see if that clears the issue.
  • PublisonPublison Posts: 12,366
    edited 2014-06-05 09:10
    BTW. Welcome to the forums! You will find everyone pretty helpful here.
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 11:55
    Okay, no dice on changing the reset method. I'll post a photo in a minute.
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 12:16
    IMG_20140605_151504.jpg


    Apologies for the quality.
    IMG_20140605_151504.jpg
    1024 x 768 - 88K
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-06-05 12:29
    I don't know what kind or reset circuit is on your USB converter but I think some circuits need a capacitor in series with the Props reset pin before they will work.

    It's hard to tell how many wires you have coming off the converter board but I just want to make sure you have the grounds connected together?

    Another common error is to switch the rx and tx lines. Remember one board's rx if the other board's tx.
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-05 12:36
    I'll try the capacitor trick. Just made sure all the serial pins are where they need to go, everything's good in that regard.
  • jazzedjazzed Posts: 11,803
    edited 2014-06-05 12:46
    What is the voltage on the RES* line when the device is connected?

    Usually, we have a differentiator transistor circuit on the Propeller RES* ... look at the Propeller Datasheet "Alternative Serial Port Connection" or other board schematics for examples.

    Did you try reversing the RX/TX pins?
  • Hal AlbachHal Albach Posts: 747
    edited 2014-06-05 12:51
    I noticed the EEPROM is not hooked up to the Propeller, I'm not sure if one is required for the Propeller to connect.
  • jazzedjazzed Posts: 11,803
    edited 2014-06-05 13:36
    Hal Albach wrote: »
    I noticed the EEPROM is not hooked up to the Propeller, I'm not sure if one is required for the Propeller to connect.


    It is only required for "stand alone" operation without downloading a program via USB (serial pins P30/P31).
  • Mercury1964Mercury1964 Posts: 15
    edited 2014-06-06 11:49
    Well, I'm all out of ideas. I'll just bite the bullet and buy a PropPlug. Thanks anyway, guys.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-06-06 12:01
    Can you show us which USB to serial device you have? I have one that looks very similar and if mine is the same as yours I'll try using it with the Prop to see if I can get it to work.
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