Simple - no response

Kirk Fraser

It has to be a simple problem I'm overlooking. F10 or F11 loads this code to my Prop with no errors but it won't show anything on serial terminal. The terminal is set to Com3 57600 and fails even after F11, hit Enable, then the Prop reset switch to give it the best chance of working. Thanks.

OBJ
  STrm : "Parallax Serial Terminal"         'Access SerTerm Object    
con
  _clkmode = xtal1 + pll16x
  _xinfreq = 6_000_000                                          ' use 6MHz crystal                                        
  CLK_FREQ = ((_clkmode - xtal1) >> 6) * _xinfreq
PUB ComTest   |  x
  STrm.Start (57600)             'Initialize timing, Rx and Tx pins for DEBUG
  repeat
    x := 26
    STrm.Str(string(13,"Test dec: "))
    STrm.Dec(x)
    STrm.LineFeed
    STrm.Str(string(13,"Test hex: ")) 
    STrm.hex(x,1)
    STrm.LineFeed 
    STrm.Str(string(13,"Test bin: ")) 
    STrm.bin(x,12)
    STrm.LineFeed 
    STrm.Str(string(10))
    waitcnt(clkfreq + cnt)

NWCCTV

F11 or F12? F12 should bring up Serial Terminal.

skylight

I'm presuming by the code above you have a 6mhz xtal fitted not 5?

Kirk Fraser

skylight wrote: »

I'm presuming by the code above you have a 6mhz xtal fitted not 5?

Yes, it takes a magnifying glass to read it but it's a 6.000

Publison

Kirk Fraser wrote: »

Yes, it takes a magnifying glass to read it but it's a 6.000

Is this a standard Parallax board? Should be 5.0 Mhz. 6.25 Mhz is another optional xtal that Parallax sells. I don't believe they sell a 6.0 Mhz.

Is your Propeller chip actually on COM3:? You may have another choice in PST.

Kirk Fraser

Publison wrote: »

Is this a standard Parallax board? Should be 5.0 Mhz. 6.25 Mhz is another optional xtal that Parallax sells. I don't believe they sell a 6.0 Mhz.

Is your Propeller chip actually on COM3:? You may have another choice in PST.

No it's a custom board with a Digi Key crystal. F7 says it's on COM3.

Publison

This code runs fine on a PPDB with 5. Mhz xtal

OBJ  STrm : "Parallax Serial Terminal"         'Access SerTerm Object    
con
  _clkmode = xtal1 + pll16x
  _xinfreq = 5_000_000                                          ' use 6MHz crystal                                        
 ' CLK_FREQ = ((_clkmode - xtal1) >> 6) * _xinfreq
PUB ComTest   |  x
  STrm.Start (57600)             'Initialize timing, Rx and Tx pins for DEBUG
  repeat
    x := 26
    STrm.Str(string(13, "Test dec: "))
    STrm.Dec(x)
    STrm.LineFeed
    STrm.Str(string(13,"Test hex: ")) 
    STrm.hex(x,1)
    STrm.LineFeed 
    STrm.Str(string(13,"Test bin: ")) 
    STrm.bin(x,12)
    STrm.LineFeed 
    STrm.Str(string(10))
    waitcnt(clkfreq + cnt)

Do you have a part number for the crystal?

Kirk Fraser

Interesting, thanks for testing.
The part number on the part is TXC 6.000c8H

This part is no longer found at DigiKey or on Google. So maybe I need to buy another one. I don't understand why it will program with it but not run.

Publison

Kirk Fraser wrote: »

Interesting, thanks for testing.
The part number on the part is TXC 6.000c8H

This part is no longer found at DigiKey or on Google. So maybe I need to buy another one. I don't understand why it will program with it but not run.

Almost looks like a part number for a Temperature compensated crystal oscillators (TCXO) which might have different capacitive characteristics.

Check out page 68 of the Propeller Manual Ver. 1.2. If it's an external Oscillator, you may want to try XINPUT instead of XTAL1.

Worth a try. Got a picture of it?

Roy Eltham

When you program the Prop it's using it's internal clock instead of the external crystal, so that would explain it working for programming but not running, if it is indeed a crystal problem.

ChrisGadd

Is the Propeller showing any signs of life at all? My very first fried Prop gave every indication of being programmed, but produced absolutely no output at all. Completely comatose, from getting my 5V and 3.3V supplies crossed.

Kirk Fraser

Thanks guys, I think that gives me enough to try for now.

The part number is likely TXCo6.000c8H but I didn't put in the small o as it looks like a square. The part looks just like a Parallax crystal.

Thanks for the ideas on how programming can work but not run.

I am sure my 3.3V is ok but I've moved since I did much work on the PCB so I have misplaced lots like spare LED's. So I'll try the program change then buy some LED's to see if the Prop works.

kwinn

Try a simple program that toggles a pin using the internal clock to see if it dead or alive.

Kirk Fraser

Confirmed, the Prop chip was dead. Thanks everyone!