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If I remember right, from the other Treadbot thread, these are homemade PCB's correct? Probably not plated thru holes unless he's got some fancy-shmancy equipment.Originally Posted by Darrel Taylor
Looking at some of the holes, they don't seem to be plated thru.
It could be reflections from the other side or something.
But that's easy enough to work around.
I'm rooting for that to be the fix..........Big bucks....no whammy's......STOP!
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the treadbot board was homemade... this ones not... i can get these made at Alberta Printed Circuits for less than it costs me to make them.. and these ones have thru-plating and better traces..
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I lost again...
I forget...aren't you 'just up the street' from me? Calgary or something?
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Me too.
<br>
DT
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yeah... . i just dont know about this board...
im in Calgary, and its -42C with the windchill and im workin outside...
Alberta Printed Circuits has a prototyping service that is two boards, double sided with thru-plating... these two boards (the top and bottom were joined together and then i cut it after) were about 3.2" X 2.5", and cost around $36 total... so each board was $13 and there made next day.... its almost not worth it for me to make them....
so i have another board the same as this one, so i might pick up another PIC and try it all again just in case i shorted something or the PIC is bad...
I have no affiliation with apcircuits, but they do good work and they have helped me through design problems so if youre looking for somewhere to make some boards, take a look at them...
eagle cad takes the schematic (which is easy to make and troubleshoot) and makes it into a board, then i email that to apc and then solder it together... there isnt a lot i can do wrong if the design is right, and the soldering is right...
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Desoldering a TQFP without a desoldering tool...heat the pins up, bend them up with something. If it's not the chip, you can probably resurrect the chip by laying it flat on a suitable spacer and flattening the pins back down with a toothpick...works for me anyways.
Yep, in Minot. You guys sent us this Alberta Clipper! And it rocks!!! Radio is saying -15F with -52F windchill (whipping up out there about 25-45MPH).im in Calgary, and its -42C with the windchill and im workin outside...
Personally, I use www.pcbexpress.com, but that's only because I've got an older version of Protel 2.7.5 and they support it. If I only had Gerber files to work with, I'd probably go with APCircuits.Alberta Printed Circuits has a prototyping service that is two boards....
Get one with an internal OSC option, like the 18F6723 or something...unless you need the CAN option. Incidentally, it's really easy to overlay an 80pin TQFP over the top of a 64pin TQFP and give you both options. When I made those 80pin TQFP -> dual 40 pin/IDC adapters awhile back, I did exactly that...made the center of the PCB able to take either an 18F6720 (64 pin) or an 18F8720 (80 pin)...same layout, just added 2 pins at each end on each side, spacing still the same, etc.etc.etc.so i might pick up another PIC and try it all again just in case i shorted something or the PIC is bad...
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the only reason i went with this PIC, is cause of microchips little PIC selector charts. it had the right number of I/Os, and a lot of memory... i think the next time, i will go with an 80-tqfp and something that will support external program memory.. then i should be able to start with the basic flashing led on internal memory, and slowly move up to more advanced...
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Well I've only got one more possibility.
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=2314&stc=1&d=120163702 7" />
Some of the via's under the PIC are Really close to the pins.
And there's no way to tell from the picture.
It would take an ohm meter to know if they're shorted or not.
But, since you're going to try the second PCB ...
If you send me the first one, I WILL find why it's not working.
<br>
DT
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well, if i get the second one going, i may send it to you if ya want... i really only need one, but its still easier and cheaper to get 2 made...
i have never tried microchips "free" trials before. i may have to do that and try a few of the different PICs.
i can program it, and it draws very little current, so i dont think the power pins are shorted. and if the I/O pins were shorted, i should still have voltage on my pin since im making every pin high.
the only problems i could see from shorting, is if i shorted an i/o to ground, and its pulled too much current. or if mclr is connected to ground or something else it shouldnt be...
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I'll send it back when I'm done. And you might want to know what's wrong before you do the second one.
On the right side of the last picture I posted, there are 2 lines.i can program it, and it draws very little current, so i dont think the power pins are shorted. and if the I/O pins were shorted, i should still have voltage on my pin since im making every pin high.
the only problems i could see from shorting, is if i shorted an i/o to ground, and its pulled too much current. or if mclr is connected to ground or something else it shouldnt be...
The bottom one is pointing to a via that is between GND and one of the oscillator pins.
If that ones shorted, it probably won't draw much current, but the oscillator won't work.
And if there's no OSC, then shorts on the other pins won't draw current either, cause they never get turned on.
But again, no way to know without an ohmmeter.
<br>
DT
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i checked both osc pins to ground with my meter when i soldered the osc... since it was so small, i checked it to make sure i didnt have any solder bridges on the OSC.
you guys are great though... if it wasnt for your suggestions, i would have given up on it long ago...
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Ok, well it's up to you.
It's just that I've been looking at it long enough that I'd really like to know what the problem is.
I have a hot air re-work station, oscilliscope DVM's etc.
<br>
DT
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Tin-whisker anyone?
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i have an oscilliscope (sorta)!!! i dont know how to use it or if it will even work... but it was fun to play around with... i want to know what the problem is so i can move on with this project...
thats my oscilliscope in the bottom right corner... its an RCA and meant for back in the tube days....
and if you look close on the shelf, you can see treadbot sitting there!!!
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i have juast gone over the board quickly, i will do it again tomorrow when i have more time, but i get:
0 ohms between all +5v traces
0 ohms between all gnd traces
30M ohms between all I/O pins and +5V
1M ohm between power and ground
4-12M ohms between all I/O pins and gnd
17M ohm between OSC2 and gnd
12M ohm between OSC1 and gnd
29M ohms between OSC2 and +5v
23M ohms between OSC1 and +5v
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I'm jealous!
I want a mill and a lathe and a drill press and a belt sander and a jig saw and a bench grinder and a ... better scope.
<br>
DT
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Don't forget the Get-Away car!I'm jealous!
I want a mill and a lathe and a drill press and a belt sander and a jig saw and a bench grinder and a ... better scope.
<br>
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Yeah, OK.
I want one of those too.
<a href="http://s163.photobucket.com/albums/t305/dragons_fire_photo/?action=view¤t=IMG_1917.jpg" target="_blank"><img src="http://i163.photobucket.com/albums/t305/dragons_fire_photo/IMG_1917.jpg" border="0" alt="Photobucket"></a>
DT
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i take it you looked at some of the other pics on my photobucket!!! what can i say... i can NEVER have too many tools!!!
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Which PIC runs that?Yeah, OK.
I want one of those too.
It's probably just a matter of time...
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there isnt any PICs in it... but i took apart a sunroof motor yesterday that im using for another robot, and it has a 16F72 in it...
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im still working on this board, i have checked the design twice more, and still dont see anything wrong with it.. when i connect the battery, i get just under 5V (and the PIC is good down too 2v). if i go across any I/O pin and gnd i get 0V and i get the same going from I/O to 5V.....
if the pins were low, i should see voltage between I/O and 5V
and if it was high i should see voltage between I/O and gnd....right??
while i have the programmer hooked up, it goes down to about 2.5V on mclr to gnd, and then when i program, it goes up to 13V. without the programmer, its at 5V
i have tried 3 different OSCs at 2 different speeds, and thats not helping, i know the power supply is good, so it has to be the PIC or the board..
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What does it mean system clock disabled? Does this mean no oscillator?
If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets.
.
Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves
.
There simply is no "Happy Spam" If you do it you will disappear from this forum.
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im not sure... i have tried it on both enabled and disabled. those were taken from the config settings of my programmer.
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System clock is actually OSCSEN.
While a program is running, you can switch the clock source from the main clock source (crystal, R/C, whatever) over to the Timer1 clock source, and back again.
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GOOD TO KNOW... i learn so much from all of you on here.... i know these PICs say they are static sensitive, but how bad is it?? should i be wearing a strap every time i think about looking at it?? or do i really need to worry about it. i know with the 16f devices i have used, they say they are static sensitive, but i have never worried about it and never had any problems...
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I haven't COMPLETELY blown a PIC up with static...YET! I know how dry it gets where you're at (remember, I'm just a bit south-east of you). My 'shop' is in the basement, usually about 20% humidity in the winter, carpet on the floor, and so on and so on.
I think, that is, THINK, the worst I've done to a PIC is blow out an output driver or two on a few PICs...and I'm not even 100% sure it was static that did it. Probably from putting them in the socket backwards, etc.
However, I've heard that the 18F's are quite a bit more static sensitive than the 16F's were, probably due to the smaller gate size on the die...not sure...don't care. As long as I don't smoke anymore, I'm all good...
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ok, i was just kind of curious... i get them from Digi-key and they come in a vacuum sealed static bag with one of those little dessicant bags in it and a humidity tester... the 16f ones, come in a little static bag thats just folded over on its self so it doesnt fall out!!
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i de-soldered the pic from the board, everything looks good under there... no solder bridges or shorts of any kind.. everything looks good... i ordered another PIC so it should be here on monday and i will try that...
i wish there was a pin compatible 16f PIC that i could throw in there and see if i could get it to work... then i would know the board is ok...
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just wondering if doing it this way decreases code size too, or if it just makes for less typing??? im working on writing some code for this project (if i can ever get the board to work) and i know it would make the code smaller to look at if i did it as above, but i think it would be harder to write since i have labeled all my ports for what they do, so when i write it, i use those "labels"....
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The hex file comes out the same, this works for very organised people, who know the subject material very well, I suggest you do it the other way with loads of comments so a year from now, when your are even better than you are now . . you can make sense of what you did as you rewrite your code . . . and you will.
JS
If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets.
.
Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves
.
There simply is no "Happy Spam" If you do it you will disappear from this forum.
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Nope, it's just a 'me-ism' thing.
I like to get as much code on a screen as I can. I hate scrolling up and down and if I've got a longer routine, I can bunch it all up in one page. It's my STYLE, if you can call it that.
Some people hate it, I mean really HATE it...too bad, so sad, don't care. If a guy has half a brain, they'd know how to use the 'replace' shortcut in WORD to put a single command on each line, and if not that, they'd at least know how to split it up. For instance, my latest project is about 1700 lines of the bunched up code, fills an 18F4620...no extra line breaks, no extra spaces, no nothing, etc. If I was to spread that out, make it "right", I estimate it would take up about 8500 lines. Forget that noise. Most of the time, my 2nd monitor is turned 90 right and Windows adjusted accordingly, like it's in 'Portrait' mode instead of the normal landscape...oh and it's 1600x1200, so that really packs it in there.
What's a guy expect for FREE help?
But like Joe said, it's all personal preference. Get your own method, stick with it, it's all good...
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posting your “problem code”
skimask’s method is perfect for his style of programming.
as Joe said: “people, who know the subject material very well”
But if anyone wants the forum to help with their code (skimask never needs help), I wouldn’t advise posting your “problem code” in this style.
-Adam-
Ohm it's not just a good idea... it's the LAW !
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'taint so!
I think the main difference is in the use of the 'Search' function here and at Google, or wherever...I'd be willing to bet I spend more time researching HOW to do stuff vs. actually doing it.
And this weekend, I could sure use some help doing some sanding, and in fact, I might even need help cleaning out all of those left over full cans of preferred beverages from the 'fridge in the basement...
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i would come give you a hand, but "unfortunately" i dont have a passport!!! and i have to wait for Puralator to deliver more parts!!!
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Passports? I thought all we needed was photo Gov't ID. I'd better do some checking. I've got a trip planned for this summer...here, thru the Black Hills/Rapid City, over to Yellowstone/Grand Tetons, up to Glacier (both U.S. and Canada versions), thru Banff and Jasper, up to Denali in Alaska, and back, sidestepping thru Yellowknife and back down.
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sounds like a good trip... i think to fly we need a passport now, but to drive you just need two pieces of government id..
so i noticed a while ago that i had shorted one OSC pin to 5v, would that have blown the OSC part of the chip???
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It's all a bit confusing... To get into Canada, I need one thing, to get back into the U.S., I need other things. Gotta do more looking.
I wouldn't think so, but...you know how far that goes...so i noticed a while ago that i had shorted one OSC pin to 5v, would that have blown the OSC part of the chip???
In external modes with crystals, the crystal/resonator is driving a differential amp inside the PIC (variable gain set by the CONFIG registers). I suppose if you had OSC1 driven to +5v and OSC2 driven to ground, you might blow it out (maximum differential = maximum output). Not really sure about that theory though, and surely not about to try it out.
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my stuff just got here a couple minutes ago, and so i soldered a new PIC to the board, and it WORKED!!!!
thanks to all the guys that had suggestions about why it didnt work, but it seems good now.. i just need to solder the top board back on (i was using jumper wires while testing)....
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That only matters if you come from the north!
If you do not believe in MAGIC, Consider how currency has value simply by printing it, and is then traded for real assets.
.
Gold is the money of kings, silver is the money of gentlemen, barter is the money of peasants - but debt is the money of slaves
.
There simply is no "Happy Spam" If you do it you will disappear from this forum.
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