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PostPosted: Fri Oct 05, 2012 12:28 pm 
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Joined: Thu Aug 30, 2012 10:50 am
Posts: 4
I don't think the PIC18F45K22 is running. I have looked at the waveforms at Q19 and the signal from Y1 looks OK, but the 25 MHz signal going to the PIC18 does not close to a square wave. It grows toward 5 VDC when Q19 is off, but is pulled low again as Q19 conducts producing a triangular-looking signal. I am looking at both signals with an FET probe. What does the Clock look like on pin 13 of U8?

Bernie
W4BGH


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PostPosted: Fri Oct 05, 2012 8:56 pm 
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Joined: Thu Aug 09, 2012 6:16 pm
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Hey Bernie,

I changed R112 to 390R and I have about 2.5VPP and nice sine wave on pin 13 of U8. I have ~4VPP from the oscillator output. Check your 3V3 DSP supply?

Cheers,

Bill
N4BKT


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PostPosted: Fri Oct 05, 2012 11:03 pm 
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Joined: Mon Jul 23, 2012 6:25 am
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Changing R112 should help, that's what I did. You can also put in a real level translator.

Jim.


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PostPosted: Fri Oct 05, 2012 11:42 pm 
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Joined: Thu Aug 09, 2012 6:16 pm
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One other thought is if you've used a sub for the FDV301N, make sure it has the internal damper diode that is not shown on the schematic. If you have a sub with a D-S reversed you could expect what you are seeing.

If you want to follow the level translator here is a useful booklet:

http://www.newark.com/pdfs/techarticles ... sBrchr.pdf

I'd be tempted to look at it with no PIC installed. There are only two parts to look at then.

GL

Bill


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PostPosted: Sat Oct 06, 2012 2:16 pm 
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Joined: Tue Oct 02, 2012 4:58 pm
Posts: 38
Bernie, I have a .3v p-p sine wave on pin 13 of U8 and a .8v p-p sine wave on pin 6 of U9. It's a nice looking sine wave but much lower in amplitude then what Bill has. I just had my initial power up today and my display is blank, only the backlight comes on. I am trying to figure out if the chips are programmed correclty. Jim programmed mine for me as I know NOTHING about programming and didn't have a programmer at the time. I have since bought a PICK2KIT and the data out of the chips the checksums for the 18F chip is 08AD and for the PIC33 it is 5916. Can anyone tell me if these are correct or at least what you have? At this point it looks like I have made a very expensive night light. lol Thanks, Eric


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PostPosted: Sat Oct 06, 2012 9:48 pm 
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Posts: 43
Hey Eric,

Not sure you can make the PICKIT 2 work on the 18F45K22 (should do the dsPIC33)- if you have not attempted to program, you probably have not munged what's on it. RE: Blank Display- Don't forget to adjust the contrast pot after booting- you can have what appears to be a blank display before adjusting it.

I have the the Olimex PCIKIT 3 clone from Mouser- but were i to buy another I would get the PICKIT3 Debug Express as it comes with some tutorials which may be helpful when it comes to making changes to code.

RE Checksums- mine for the PIC18 will be different as I've made a few changes for my SI570 cal which you'll need to do as well so each unit will be unique once calibrated.

Don't worry about not knowing stuff: When you're green, you're growing! - 73 es GL with your build.

Bill
N4BKT

ecpilot wrote:
Bernie, I have a .3v p-p sine wave on pin 13 of U8 and a .8v p-p sine wave on pin 6 of U9. It's a nice looking sine wave but much lower in amplitude then what Bill has. I just had my initial power up today and my display is blank, only the backlight comes on. I am trying to figure out if the chips are programmed correclty. Jim programmed mine for me as I know NOTHING about programming and didn't have a programmer at the time. I have since bought a PICK2KIT and the data out of the chips the checksums for the 18F chip is 08AD and for the PIC33 it is 5916. Can anyone tell me if these are correct or at least what you have? At this point it looks like I have made a very expensive night light. lol Thanks, Eric


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PostPosted: Sun Oct 07, 2012 8:14 am 
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Joined: Tue Oct 02, 2012 4:58 pm
Posts: 38
Hi Bill and thanks for the information. I was asking about checksums to just verify that the chips had a good program loaded in them and didn't get corrupt somehow. I bought the PIC2KIT per Jim's recommendation fairly early on in the project and it seems to recognize and read the 18F with no problems. I have also written to it but have no idea if all went correctly but the PICkit2 v2.61 software that came with it said it performed the task successfully.
After reading your information in the firmware section of th DSP-610 on google sites, I decided to download MPLAB IDE 8.87 and try that approach. When I read the DSP PIC18 workspace file into MPLAB and do the "project build all" command, I get the following results:
Debug build of project `C:\Users\User\Documents\DSP-610\DSP-610 18F Baseline Code\DSP-610 PIC18.mcp' started.
Preprocessor symbol `__DEBUG' is defined.
Sun Oct 07 08:46:56 2012
----------------------------------------------------------------------
Clean: Deleting intermediary and output files.
Clean: Deleted file "C:\Users\User\Documents\DSP-610\DSP-610 18F Baseline Code\DSP-610 PIC18.mcs".
Clean: Done.
Couldn't locate build tool. Check tool locations.
----------------------------------------------------------------------
Debug build of project `C:\Users\User\Documents\DSP-610\DSP-610 18F Baseline Code\DSP-610 PIC18.mcp' failed.
Preprocessor symbol `__DEBUG' is defined.
Sun Oct 07 08:46:57 2012
----------------------------------------------------------------------
BUILD FAILED

So it looks like I am not having any luck with that approach either. Seems I am missing the build tool. Time to do some more reading!


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PostPosted: Sun Oct 07, 2012 10:59 am 
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I have changed R112 to 390 ohms. The clock signal to the PIC18F45K22 still looks pretty bad, but it must be good enough because the processor seems to be running as evidenced by a functional LCD display. By the way, the suggestion to decrease the display contrast was very helpful. Thanks for the suggestions.

Bernie
W4BGH


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PostPosted: Sun Oct 07, 2012 4:14 pm 
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Joined: Tue Oct 02, 2012 4:58 pm
Posts: 38
Yes, it worked for me also. The contrast pot has to be all in one direction but now my display is operational as well as the switches. The output from U4 looks terrible so I hve to think that IC is toast. I did get it very hot trying to solder it so I have a feeling that might have ruined it. If someone could post a picture of the output of U4 that might help me determine if mine is bad. I do have some hiss coming from the speaker and the RF gain seems to be working as it changes the S meter in the display. The AF gain doesn't seem to be doing anything at this point. Thanks for the advice Bill, it is MUCH appreciated.


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PostPosted: Sun Oct 07, 2012 6:45 pm 
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Joined: Thu Aug 09, 2012 6:16 pm
Posts: 43
Don't buy another AD9833 yet. I do have a photo of the output of U4 posted in another thread- and a link to the AD simulator web page. It does not look like a sine wave prior to the filtering- check the output at the filter out. I thought I had toasted mine too- even removed and refit it. If you have 2.5V on C2.5 and ~3.6V cmp it probably is working- you need at least 50 MHz scope to see the output well.


ecpilot wrote:
The output from U4 looks terrible so I hve to think that IC is toast. I did get it very hot trying to solder it so I have a feeling that might have ruined it. If someone could post a picture of the output of U4 that might help me determine if mine is bad.


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