Program loading but not running

kylekenj

I created a program that would run on the quick start board so I build a PCB for to run it using a minimum board like http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/PropellerHardwareConnections.pdf. I was able to get the first board I built to read the chip and program after fixing my connections but it fried because I wasn't filtering my power supply. I fixed that on my next board and the propeller will read off the prop plug and I can program the ram and the eeprom but the program won't work I then tried to take a simpler program and used this code from ganster gadget.

CON
_clkmode = xtal1 + pll16x
_xinfreq = 5_000_000

OBJ
pst :"Parallax Serial Terminal"
PUB main
pst.Start(115200)
dira[0] :=1
repeat
outa[0] :=1
pst.str(string("LED ON",13))
waitcnt(clkfreq+cnt)
outa[0] :=0
pst.str(string("LED OFF",13))
waitcnt(clkfreq + cnt)

I checked everything with a voltmeter and everything looks good coming in. It loaded but doesn't seem to work. I am not sure what is wrong.

JonnyMac

You have a hardware problem because the code runs fine. I'm running this on a QuckStart. Note, too, that you should use the [ code ] and [ /code ] tags (remove spaces).

con

  _clkmode = xtal1 + pll16x
  _xinfreq = 5_000_000
  

obj

  pst : "Parallax Serial Terminal"

  
pub  main

  pst.Start(115200)
  dira[16] :=1
  
  repeat
    outa[16] :=1
    pst.str(string("LED ON", 13))
    waitcnt(clkfreq+cnt)
    outa[16] :=0
    pst.str(string("LED OFF", 13))
    waitcnt(clkfreq + cnt)

average joe

Sounds like a fried PLL. Try

on

  _clkmode = xtal1
  _xinfreq = 5_000_000
  

obj

  pst : "Parallax Serial Terminal"

  
pub  main

  pst.Start(115200)
  dira[16] :=1
  
  repeat
    outa[16] :=1
    pst.str(string("LED ON", 13))
    waitcnt(clkfreq+cnt)
    outa[16] :=0
    pst.str(string("LED OFF", 13))
    waitcnt(clkfreq + cnt)

If that runs, it's confirmed fried PLL

Note to the guys @Parallax.... Please get rid of these examples that do not show bypass caps!!! I've seen several posts about this issue recently. Might help the "Beginner Friendly" image

MagIO2

Try to run it with internal clock (maybe using a smaller baudrate). If this works there is probably something wrong with the crystal. You can also try out other xtal - settings.

Dave Hein

Post your schematic and pictures of your board. You may still have a problem with the power voltage going to the Prop. The power may be clean enough to run one cog, but when the program runs it starts up a second cog, which increases the current usage. You might need a few bypass caps, or there may be something else wrong with the power conditioning.

kylekenj

Thanks a ton guys. It was the lack of bypass caps. I used the tips to check. Sample program worked and my other program works great now.