Have i killed my quickstart? only drawing 2v from USB

Dwayne Dibbley · 2011-12-07 10:34

Hi

i was in the middle of running a program when the quickstart dropped off the usb, and now wont connect ( be seen as a com port ) measuring the voltage it is only drawing 2v from the pc and only the green power led lights up . reset button also does nothing

any ideas on what to check

Thanks

Phil Pilgrim (PhiPi) · 2011-12-07 10:44

Your voltage might be low because the board is drawing too much current. Do you have any other components connected to the QS board that might be overloading the USB power?

-Phil

Dwayne Dibbley · 2011-12-07 10:45

Nothing connected to QS

here is the coded that was loaded

con  _clkmode = xtal1 + pll16x                '
  _xinfreq = 5_000_000                     '


obj
                                                        '2 Cog here 
  uarts         : "pcFullDuplexSerial4FC"               '1 COG for 4 serial ports
  gps           : "GPS_IO"                              'no COG required
  
var
  long  stack[50]                                       'requires stack of at least 32
  long  cog


pub main | time
  uarts.Init
  uarts.AddPort(0,31,30,{
}   UARTS#PINNOTUSED,UARTS#PINNOTUSED,UARTS#DEFAULTTHRESHOLD, {
}   UARTS#NOMODE,UARTS#BAUD115200)                      'Add debug port
  uarts.AddPort(1,4,UARTS#PINNOTUSED,{
}   UARTS#PINNOTUSED,UARTS#PINNOTUSED,UARTS#DEFAULTTHRESHOLD, {
}   UARTS#NOMODE,UARTS#BAUD115200)                      'Add gps port
  uarts.Start                                           'Start the ports
  
  uarts.str(0,string("Starting",13))
  gps.Init(1)                                           'use Init and then uses BackGround cog
                                                        'to process GPS receive characters
                                                        'Note the background cog isn't running
                                                        'but it doesn't seem to affect us sending
                                                        'commands to gps
  
  cog := cognew(BackGround,@stack) + 1                  'Start the background Cog


  time := cnt + clkfreq*2
  repeat
    if time < cnt                                       'every 2 sec check gps and camera
      time := cnt + clkfreq*2
      if byte[gps.valid] == "A"                         'if gps is tracking pring where we are
        GPS_Output                                      


PRI GPS_Output
  uarts.str(0,string("GPS available",13))
  uarts.str(0,string("Latitude "))
  uarts.str(0,gps.latitude)
  uarts.str(0,string(", Longitude "))
  uarts.str(0,gps.longitude)
  uarts.str(0,string(", GPS Altitude "))
  uarts.strln(0,gps.GPSaltitude)
  uarts.str(0,string("Speed "))
  uarts.str(0,gps.speed)
  uarts.str(0,string(", Heading "))
  uarts.str(0,gps.heading)
  uarts.str(0,string(" "))
  uarts.str(0,gps.N_S)
  uarts.str(0,gps.e_w)    
  uarts.str(0,string(", Satellites "))
  uarts.strln(0,gps.satellites)
  uarts.str(0,string("Time GMT "))
  uarts.str(0,gps.time)
  uarts.str(0,string(", Date "))
  uarts.strln(0,gps.date)


pub BackGround
'Process gps and camera receive characters
'minimize processing in this cog, i.e. dont send to serial ports e.g. debug
'dont call waitcnt, etc. Dont call blocking receives from serial ports - use rxcheck
  repeat
    gps.GetNMEALine

Mike Green · 2011-12-07 11:09

How is the GPS device connected?

Dwayne Dibbley · 2011-12-07 11:13

Mike Green wrote: »

How is the GPS device connected?

3.3v off pin 38 and 39, GPS TX to pin 5 (p4) RX

I have now connected a 9v source to 39 and 40 and have a stable 3.3v, i have also connected a external ttl usb serial to pins 35 and 33 and when conneced to the parallax serial terminal is looks like its dumping loads a garbage out, but still no reset or chip detected

Thanks

hover1 · 2011-12-07 13:25

Dwayne Dibbley wrote: »

3.3v off pin 38 and 39, GPS TX to pin 5 (p4) RX

I have now connected a 9v source to 39 and 40 and have a stable 3.3v, i have also connected a external ttl usb serial to pins 35 and 33 and when conneced to the parallax serial terminal is looks like its dumping loads a garbage out, but still no reset or chip detected

Thanks

I'm confused.

Phil asked if there was anything connected, you said no. Then you told Mike there was a GPS connected, (Parallax part number?). Which GPS? What supply voltage does it need?

Most GPS communicate at 4800 baud. Looks like you may be trying to read at 115400.

Dwayne Dibbley · 2011-12-07 13:32

sorry for the confusion, yes there was a gps connected ( sparkfun venus 3.3v ) this has worked fine before on other code, i was trying to get the 4 serial port single cog running using the above code and just f11 loaded it to the quickstart and then f12 opened the terminal window then windows reported the com port unplugged ( USB ) and now i cannot talk to the quickstart

i should have said with nothing connected to the quickstart it still is not recognised

Thanks again

Rayman · 2011-12-07 15:10

I'd be suspicious that you overloaded your USB port... If you only see 2V with USB connected, sounds like USB power has shut down...

GPS units can draw a lot of power, maybe that's why...

Anyway, I'd try a different USB port. A powered USB hub is the best idea...

hover1 · 2011-12-07 15:31

Rayman wrote: »

I'd be suspicious that you overloaded your USB port... If you only see 2V with USB connected, sounds like USB power has shut down...

GPS units can draw a lot of power, maybe that's why...

Anyway, I'd try a different USB port. A powered USB hub is the best idea...

I thought the same, but I saw the Parallax GPS's only draw about 70ma. But.. plugging a wrong wire into a connector adjacent to to correct one on the QuickStart might release the super secret internal smoke.

Dwayne Dibbley · 2011-12-13 10:45

Well i left it unplugged for the last week and thought i would try it again today, plugged it in and was able to download a test program so now all working again

Thanks

Have i killed my quickstart? only drawing 2v from USB

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