Dangerous Prototypes

General Category => General discussion => Topic started by: chr on December 16, 2011, 06:41:11 pm

Title: Sure Electronics PICkit 3
Post by: chr on December 16, 2011, 06:41:11 pm
Hey everyone,
some time ago there was this (http://http://dangerousprototypes.com/2009/08/22/sure-electronics-pickit2-clone-teardown/) blog post about the PICkit 2 clone. A few weeks ago I bought the PICkit 3 clone from the same manufacturer - here is my experience with it.

Until then my experience with PIC programmers was a homebuilt JDM serial programmer (about a decade ago...) and a loaned Microchip ICD 3 that I used for an uni project.


First impression

This clone is really cheap - I could get about two for the price of a single genuine Microchip PICkit 3. Nevertheless it comes in a sturdy box and includes both a single row 6-pin female to female and a 6-pin modular connector ICSP cable. There's also a 1x6 pin male header, a right-angle 1x6 female header and the Mini-USB cable included.

The case looks pretty much like the one in the blog post linked above; it seems reasonably sturdy and to open it you just have to slide your fingernails along the groove. The pcb is held in place by four thin plastic posts. To separate it from the upper shell you might have to push a bit on the leds from the outside - they sit very tight in their cut-outs.

Because of the black solder mask it's a bit hard to make out how much flux residue there's on the board. Especially on the bottom, around the pins of the buttons there was definitely residue. I encountered maybe one or two bits of stray solder but all in all I've seen worse. The socket you connect the programming cable to seems a bit weak; applying small pressure is enough to bend it upwards and maybe snap the pins if this happens too often. Although, with the case in place bending it upwards is not really possible.


Use

MPLAB v8 was already installed on my machine, so I just had to connect the clone and select it as a PICkit 3 programmer/debugger. At that time I had a board with a PIC24F nearby and sure enough, after MPLAB had finished downloading the appropriate firmware, almost everything worked as it should.

There was one bit that was bugging me. In MPLAB there's a dialog box for the PICkit where you can configure the Programmer-To-Go feature, enable power supply by programmer and monitor V[sub:]DD[/sub:] of the connected board. Well, the reported voltage was not correct. Instead it reported approx. V[sub:]DD[/sub:] x 2.2.

It seems that MPLAB actually doesn't care if the reported V[sub:]DD[/sub:] is too much for the selected device but if you use the programmer to supply power the reported V[sub:]DD[/sub:] can't be too much below the set value. If it is, MPLAB reports that it has recognized a short circuit on either V[sub:]DD[/sub:] or V[sub:]PP[/sub:].

Next, I tried the clone on an old PIC16 which needs about 13V V[sub:]IHH[/sub:] to enter programming mode. MPLAB informed me that it can only read 00000000 as device id, which isn't what it was expecting... Long story short - the programmer is only supplying about 6.1V V[sub:]pp[/sub:].


Contact with Sure Electronics

... was a bit difficult. In the package there was a small card with an email address on it in case there were any problems. After a few days of waiting and trying a different way of contact I managed to get a response.

I explained the problems I was experiencing and suggested that there might be a hardware problem with programmer but as answer I got sent some links I had already seen entering the MPLAB error message into Google. I also had to confirm a few times that I had indeed connected the ICSP correctly (an understandable question but I think one time is enough).

Next I was provided with a firmware file (I assume in case the PIC24 inside the clone had been corrupted) which I unfortunately couldn't try as I didn't have the ICD 3 anymore.

After that a suggestion for addition of an resistor to the PCB arrived but doing this changed neither the wrong V[sub:]DD[/sub:] display, nor the inability to generate a high enough V[sub:]PP[/sub:].


Fixes/Improvements

A schematic of the genuine PICkit 3 is provided in Microchip's DS51795 document. The clone does not deviate too much from this.

My first bet was a wrong reference voltage (VREF_2.5). It turned out to be alright.

Next, I backtracked my way from the ICSP connector to RB2, where V[sub:]DD[/sub:] is sensed. There's a voltage divider involved where VDD_FBACK originates. On the clone these two resistor had different values compared to the schematic but they did have the correct ratio. Tweaking this ratio quickly lead to a correct V[sub:]DD[/sub:] display in MPLAB.

The situation for V[sub:]PP[/sub:] is similar. It also has an associated voltage divider and careful changes combined with monitoring this voltage during the phase were MPLAB tries to read the device id got me where I wanted to be.

If you want the clone to supply power it also makes sense to modify the gain of the amplifier which is tasked with regulating VDD_INT; this was a bit off on my device.

The dual colour status LED was not working on it's green side, I'll also have to replace this one.

I'm not sure why these fixes were necessary in the first place although I can imagine a reason or two...


Conclusion

I still think that the price/performance ratio for this clone is not bad but if I knew that I had to invest a few hours looking for the cause of this defects, writing emails and questioning if the problem was maybe even PEBKAC on my end I would have bought the genuine product.

Email contact with Sure Electronics was not exactly what I hoped for - there was this initial delay and in the end I had to find a solution myself - but I do have to say that the person I was communication with was polite and relatively fast to answer (after communication was established).

I hope that some of you have already tried out either the Microchip PICkit 3 or a clone and can provide some insight. In particular I would like to know if you've encountered similar (or different) problems and if you stumbled upon any difference between the Microchip schematic and a genuine PICkit 3.



EDIT: The socket for the programming cable is indeed not very sturdy. It's pins just snapped.
Title: Re: Sure Electronics PICkit 3
Post by: Sjaak on December 16, 2011, 07:17:51 pm
I got the same as you, but without much of the trouble. the quality is a bit low (the shell keeps falling apart, the connector is weak) but what you can expect for that amount of money. Also the powersupply is a bit too weak, but setting it a bit higher does help (and work better :))
Title: Re: Sure Electronics PICkit 3
Post by: ian on December 16, 2011, 07:28:54 pm
Thanks for the review.  May I post the entirety on the blog?
Title: Re: Sure Electronics PICkit 3
Post by: chr on December 16, 2011, 07:51:24 pm
[quote author="Sjaak"]I got the same as you, but without much of the trouble[/quote]
So do you get the correct target voltage displayed on the Status Page in the PICkit Settings dialog?

[quote author="ian"]May I post the entirety on the blog?[/quote]
Sure.
Title: Re: Sure Electronics PICkit 3
Post by: ian on December 17, 2011, 09:10:51 am
Thanks!
Title: Re: Sure Electronics PICkit 3
Post by: dpropicweb on December 17, 2011, 11:32:04 pm
My Sure Electronics PICkit 3 doesn't seem to have these issues. Curiously, my PICkit3 case is identical to their PICkit2 case, except 3 replaces 2 and their name and logo are omitted altogether. Is that the same as your case?
Title: Re: Sure Electronics PICkit 3
Post by: chr on December 19, 2011, 01:06:50 pm
[quote author="dpropicweb"]My Sure Electronics PICkit 3 doesn't seem to have these issues. Curiously, my PICkit3 case is identical to their PICkit2 case, except 3 replaces 2 and their name and logo are omitted altogether. Is that the same as your case?[/quote]
Yes, my case looks exactly like you describe it; the font for the "PICKIT" text was also changed. It matches the photo on their web store.

I suppose that hardware wise my device is identical to the ones you and Sjaak received. Could either of you check R36/R41? They are located to the left on the bottom side of the pcb. On mine these were 4k7/2k7 at the time I received the device (before modification).

If these are indeed the correct values then my next guess is that somewhere (maybe on the 25lc256) are calibration constants which are applied to the raw ADC values. If theses constants were wrong that would explain why I was getting wrong values.
Title: Re: Sure Electronics PICkit 3
Post by: erdabyz on December 19, 2011, 05:35:39 pm
For those that might be curious, here are two pictures of my own PK3-clone from sureelectronics:
(http://http://i.lulzimg.com/225a2825cf.jpg)
(http://http://i.lulzimg.com/d3b333ac69.jpg)


I've had it for more than a year or so now, and I'm very happy. I also have issues with the voltage regulator, as it puts out a lower voltage than it should. I had problems with a PIC32 which wouldn't get programmed at the 3.3V setting because it was only putting out 2.9V. It worked after setting it to 3.6V (3.2 real volts)

As you see my resistors are also 4k7 and 2k7
Title: Re: Sure Electronics PICkit 3
Post by: Sjaak on December 19, 2011, 10:19:38 pm
Sorry for the late reply but mine are also 4k7 and 2k7.
Title: Re: Sure Electronics PICkit 3
Post by: Xykon on July 15, 2012, 02:49:04 pm
I also just ordered a PicKit3 clone (http://http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=221060493305+) from this seller, looks like it's the cheapest with free shipping.

I already have the iCP02 PicKit2 clone from piccircuit.com (http://http://www.piccircuit.com/shop/pic-programmer/55-icp02-usb-pic-programmer.html) so I'm not too worried about flashing older 13V stuff but I came accross a new project where the PicKit2 clone just wouldn't work.

For now I'm planning to use the new PicKit3 only for when it really is required but I'm actually hoping I might finally one day ditch the iCP02 or reprogram it into something else as you have access to the programming headers once you remove the heatshrink coating.

I'm just wondering, beside quality and the above mentioned problems, if there is anything else to look out for?

And finally, I'm starting to think about also getting the ICD3 kit. Are there any cheap clones for this as well or is that a Microchip propriotary design?

P.S. Here is a pic (from the ebay site linked above) of the PicKit3 clone for anyone else who might be interested....

(http://http://www.sure-electronics.net/measure,tools/DB-DP005_2_b.jpg)
Title: Re: Sure Electronics PICkit 3
Post by: ian on July 25, 2012, 05:24:19 pm
Has it arrived yet? Are you happy with it?
Title: Re: Sure Electronics PICkit 3
Post by: Xykon on August 02, 2012, 12:41:42 am
I just got mine two days ago. It does seem to do what it's supposed to do but I didn't have time to fully review the thing or even open the case. Once I had a chance to play with this thing for more than a few minutes I'll write a review on my new blog (http://http://www.tiny-dev.com).
Title: Re: Sure Electronics PICkit 3
Post by: dabyd64 on September 20, 2012, 08:44:28 pm
My pickit3 fall yesterday, due that some resistors became lost. I suppose the were bad soldered.
I came here from google image search, but the image links are broken.
Could anyone reupload that nice HQ pcb images? They would be very useful for me for repairing it, knowing what were there..
thanks in advance :)
Title: Re: Sure Electronics PICkit 3
Post by: dpropicweb on September 20, 2012, 11:10:42 pm
The image(s) linked above are not broken, but I'm not sure they'd help you anyway.
Better to tell us which R numbers on the PCB are now missing and someone can tell you what values you need.
Title: Re: Sure Electronics PICkit 3
Post by: arakis on September 21, 2012, 10:34:46 am
There is also a schematic in the origina PicKit 3 manual, although I am unsure if the clone is 100% schematic compatible, what I mean is, I am unsure if the part nameing on the clone is identical to the original
Title: Re: Sure Electronics PICkit 3
Post by: dabyd64 on September 21, 2012, 03:27:39 pm
the sure clone differs pretty much from the original pickit3 in the power supply and voltage regulators for vpp/vdd etc.
The images I was requesting are from the erdaviz user, post viewtopic.php?t=3297&p=42496#p32910 (http://dangerousprototypes.com/forum/viewtopic.php?t=3297&p=42496#p32910)
In google images showed as 5MP...
hxxp://i.lulzimg.c0m/225a2825cf.jpg (http://hxxp://i.lulzimg.c0m/225a2825cf.jpg)
hxxp://i.lulzimg.c0m/d3b333ac69.jpg (http://hxxp://i.lulzimg.c0m/d3b333ac69.jpg)
I changed to hxxp AND c0m because the forum treated my post as spam :/

The resistor and capacitor lost are in the back side, labelled C16, R42.
Also C24 is not there, but it seems that nothing was there (no solder marks).
I think its a feedback for the VUSB_OK tag, so maybe its a simple 10k resistor and 10nF cap for stability.

Anyway, if I could get a photo of the pcb back side, it would be nice, to check if something else has drop too.
Thanks
Title: Re: Sure Electronics PICkit 3
Post by: erdabyz on September 21, 2012, 06:50:34 pm
(http://http://i.imgur.com/OvpeH.jpg)
(http://http://i.imgur.com/5ejWW.jpg)
Title: Re: Sure Electronics PICkit 3
Post by: dabyd64 on September 23, 2012, 02:51:15 am
A thousand thanks!! (better 50.000) I will see. There are more things lost from what I thought.
I was able to get it working a bit, in a strange way, still  not recognizing the pic attached and also sometimes not recognized as usb device.
I will have to check and resolder everything, maybe more components are partially soldered.

By the way, this clone has a bunch of bugs...unless you really need to save the money...get it from microchip.
At least they could have made some document for the users who had bought it could fix them themselves (VCC and VDD voltages accuracy and offsets, also the regulator for internal 3.3V gives 3.05V due bad resistor divider...)

If I can't fix it at the end, at least I will have been fighting with it until then, :-)

Thanks again dude!
Title: Re: Sure Electronics PICkit 3
Post by: dpropicweb on September 23, 2012, 04:50:43 am
[quote author="dabyd64"]
I will have to check and resolder everything, maybe more components are partially soldered.
[/quote]

I'd contact Sure Electronics. They replaced a faulty PICkit2 (one of four I'd bought from them) with no hassles.

Quote
By the way, this clone has a bunch of bugs...unless you really need to save the money...get it from microchip.

Of the hundreds they sell, there's bound to be a few duds. My Sure PICkit3 has worked perfectly for the last two years, except for the same issues as the original Microchip PICkit3.
Title: Re: Sure Electronics PICkit 3
Post by: arakis on September 24, 2012, 11:49:30 am
[quote author="dabyd64"]A thousand thanks!! (better 50.000) I will see. There are more things lost from what I thought.
I was able to get it working a bit, in a strange way, still  not recognizing the pic attached and also sometimes not recognized as usb device.
I will have to check and resolder everything, maybe more components are partially soldered.

By the way, this clone has a bunch of bugs...unless you really need to save the money...get it from microchip.
At least they could have made some document for the users who had bought it could fix them themselves (VCC and VDD voltages accuracy and offsets, also the regulator for internal 3.3V gives 3.05V due bad resistor divider...)

If I can't fix it at the end, at least I will have been fighting with it until then, :-)

Thanks again dude![/quote]

The Olimex one I have, work's like a charm. Only problem  had with it, was that due to a power outige during a firmware upgrade, my kit3 stopped working, I contacted Olimex, and they were super nice, and sen;t me the hex file to reflash it...

also a good Idea is to download the entire flash of your Pickit3 onto a hard drive for quick fixes to similar problems..
Title: Re: Sure Electronics PICkit 3
Post by: dabyd64 on September 26, 2012, 04:56:11 pm
Well, the problem is that I had bought it in January, and the Sure-Electronics warranty is only 90 days.
I claimed that anyway its had strange problems from the start, and that resistors where bad soldered at the factory, it's not normal than a small drop makes such damage... But no way.
I also requested the real schematic, and they sent me a Microchip's pickit 3 copy! The should think that I'm stupid...Thanks for nothing!
So, I'm going to try doing the schematic from the PCB. If I finish it I will publish them!
Title: Re: Sure Electronics PICkit 3
Post by: dheadz on February 04, 2013, 06:34:10 pm
Hi guys,
Luckily I found this forum :) It looks like I have joined the club, since my PK3 doesn't work as I would. Unfortunately, there are many deviates to the original schematic.
I made a few check, and at first the 3.3V was only 3.1V so I had to replace the R17/R24 pair with 330R/560R, and I get 3.357V : perfect for me. Additionally, before the "3.3V-case" the Vdd voltage was rather different (both the measured and the signed in MPLAB), but after look much better (but not perfect - only ~0.2V alteration).
My more painful problem is that it is not possible for me to read/program a 18F25K80 PIC, maybe because of the 9V programming voltage.
So how would it be to check the correct Vpp voltage? chr: in which way did You measure the 6.1V Vpp?
Title: Re: Sure Electronics PICkit 3
Post by: neslekkim on February 08, 2013, 10:39:44 am
I got my pickit3 from sure now, and it's different from the pictures others posted here, strange.
Don't know if it works since I have newer tried an pic/pickit before.
Title: Re: Sure Electronics PICkit 3
Post by: arhi on February 10, 2013, 11:32:49 pm
it is probably new - fixed version. if you have a problem with it let us know but it should work
Title: Re: Sure Electronics PICkit 3
Post by: dheadz on February 12, 2013, 09:58:47 am
Mine is the same - green 'Lötstop', but with problems on the board...see my previous post.
Title: Re: Sure Electronics PICkit 3
Post by: Hornet125 on March 28, 2013, 05:16:16 am
I have a Sure E Pickit 3 and see my power voltage off as well.  I need to adjust the resistors also at R17/R24.  Mine shows 3.06V now and I have had problems ID'ing some PICs already.

"I made a few check, and at first the 3.3V was only 3.1V so I had to replace the R17/R24 pair with 330R/560R, and I get 3.357V : perfect for me. Additionally, before the "3.3V-case" the Vdd voltage was rather different (both the measured and the signed in MPLAB), but after look much better (but not perfect - only ~0.2V alteration)."

 
From Char on another post: "Next, I backtracked my way from the ICSP connector to RB2, where VDD is sensed. There's a voltage divider involved where VDD_FBACK originates. On the clone these two resistor had different values compared to the schematic but they did have the correct ratio. Tweaking this ratio quickly lead to a correct VDD display in MPLAB.

The situation for VPP is similar. It also has an associated voltage divider and careful changes combined with monitoring this voltage during the phase were MPLAB tries to read the device id got me where I wanted to be."

Anyone know which Rs on the Sure Electronic Board are the dividers above?

Thanks!
Title: Re: Sure Electronics PICkit 3
Post by: tataH on October 08, 2013, 10:19:52 pm
Good day to ya all

(New to this forum)
Wanted to buy an PK3 after using a PK2 for some times. And after reading this thread I thought was ok to go with the Sure. But sadly the  problems aren't over yet. Bought this one on Ebay just a few weeks ago.
 
Experiencing some of the same problems:
- not able to supply power to the PIC
- Mismach with PIC id's
- Connecting to USB lights up a christmas tree: all the led are on (Status = red) and the PK is not registered by the OS (Chrubuntu). Work around: This can sometimes be solved by holding down the button for a few seconds, but it looks like MPLABX also needs to be running. Sometimes this has to be done several times.

But programming works (on a 16F690) when board has external power.

I will try to make some pictures this weekend and see if this is the "black solder mask" or the 'green solder mask" version and check the values of the resistors.

GJ
Title: Re: Sure Electronics PICkit 3
Post by: dpropicweb on October 09, 2013, 11:42:35 am
> Experiencing some of the same problems:
> - not able to supply power to the PIC

Applies equally to Microchip's original PICkit 3.

- Mismach with PIC id's

Ditto.

> - Connecting to USB lights up a christmas tree

I've not heard of this one before, but it may be a symptom of the power issue below.

> But programming works (on a 16F690) when board has external power.

Yep - the PICkit 3 manual contains a boxed note stating:

"The PICkit 3 programmer/debugger is powered through its USB connection. The target is powered from its own supply. Alternatively, the PICkit 3 can power the target only if the target consumes less than 30mA."

In another place in the manual it also states that powering the target from the PICkit 3 is not recommended for general usage as it imposes more current demands from the USB power system derived from the PC.

And in yet another:

"The desired method is for the target to provide VDD since it can provide a higher  current. The additional benefit is that plug-and-play target detection facility is  inherited, i.e., MPLAB IDE will let you know in the Output window when it has detected the target and has detected the device."

The PICkit 3 itself requires more than 100mA from the USB port and there's the usual warnings about USB cable length, using unpowered hubs, keyboard connections, disabling USB power saver modes etc.

You don't mention whether you're programming a bare chip or a chip in circuit etc. The Microchip Forums are awash with Microchip original PICkit 3 horror stories with the advantage that Microchip happily send replacements only to have the end users experience the same symptoms with the replacements, but at least you then know it's not your particular PICkit 3 to blame and the problem probably lies elsewhere :-)

Oh, and if you ever program a PIC32 with the PICkit 3, beware of accidentally pressing the function button or you will brick your PIC32 chip permanently.
Title: Re: Sure Electronics PICkit 3
Post by: Sleepwalker3 on October 09, 2013, 11:54:46 am
[quote author="dpropicweb"]
Oh, and if you ever program a PIC32 with the PICkit 3, beware of accidentally pressing the function button or you will brick your PIC32 chip permanently.[/quote]


Really?! Why is that? Thanks for the tip, might have had a bricked dev board.
Title: Re: Sure Electronics PICkit 3
Post by: dpropicweb on October 09, 2013, 12:32:26 pm
> Really?! Why is that? Thanks for the tip, might have had a bricked dev board.

The "programmer to go" function is triggered with no image in the PTG EEPROMs, so it wipes the chip completely including the device id. Microchip acknowledged the issue in September 2011 and allegedly said they'd fix it as a priority with a firmware upgrade, but the last time I was programming PIC32s (May 2012) it was still happening. I've not seen anything since apart from the warnings about it, but then I've not been programming PIC32s and I haven't been looking.
Title: Re: Sure Electronics PICkit 3
Post by: neslekkim on October 09, 2013, 12:40:10 pm
They say that if you press the Program to Go button when you DON'T have image in the programmer, that you destroy the pic32.. read the warning here:
https://www.olimex.com/Products/Duino/P ... e-hardware (https://www.olimex.com/Products/Duino/PIC32/PIC32-PINGUINO-OTG/open-source-hardware)
Title: Re: Sure Electronics PICkit 3
Post by: Sleepwalker3 on October 09, 2013, 03:19:52 pm
Ahhhh, I see. So I'm guessing you can't fudge the PicKit3 to just believe a certain Chip ID when the chip isn't telling?  Surely you would think the chip ID would be hardwired into the thing so that it could never be wiped, I can't see any value in having a chip ID that can be overwritten.  Thanks for the info guys.
Title: Re: Sure Electronics PICkit 3
Post by: Sleepwalker3 on October 09, 2013, 03:28:53 pm
Doubt I'll ever use the PTG feature, so might just remove the button or cut the track.
Title: Re: Sure Electronics PICkit 3
Post by: MaurizioT on June 18, 2017, 12:30:10 pm
Hi guys,
I am a newbie.

Sorry but I didn't found a way to write a post, I receive a message but I am not writing link or spam.

I would like to post another solution.

Greetings
Title: Re: Sure Electronics PICkit 3
Post by: MaurizioT on June 19, 2017, 11:09:03 pm
Hi guys,
I bought this small programmer in the past but I am using it frequently only now.
The problem described is true, it is relative only to Sure clone and the solution proposed is good.
My programmer has the same green printed circuit board present in photo posted before from neslekkim.

However I have solved it changing only one resistor.
Near AMS1117, you can found two resistor, the couple R17/R24 having 470/680 ohm in the original Sure.
It is enough to exchange the 680 ohm resistor with one of 750 ohm, in this way the 470 ohm resistor remain unchanged.
I have used one resistor with a 1206 package because I haven't a 0603 available but you can use also 0805, it fit the same.
Before the modification I get 3,095V, after this smart modification then I measure 3,286V using my Fluke 177 multimeter and it is working fine.
Who like the perfection and would like to measure exactly 3,3V then he must select one resistor of 755 ohm before solder it.

About the voltage reference called VREF_2.5 (it is half of 5V therefore 2,5V) is perfect, I measured 2,500V on pin 16 of PIC microcontroller.

Greetings to all!
Title: Re: Sure Electronics PICkit 3
Post by: dpropicweb on June 20, 2017, 12:35:56 am
Thanks for that information MaurizioT. Curiously, my Sure PICkit 3 didn't need any mods, but I see a number of others did.
Title: Re: Sure Electronics PICkit 3
Post by: MaurizioT on June 20, 2017, 10:19:42 am
There are different versions of PCBs.
Also there are some of that version have different components (as value).
Maybe were assembled at different times or from different manufacturers.

[quote author="dpropicweb"]Thanks for that information MaurizioT. Curiously, my Sure PICkit 3 didn't need any mods, but I see a number of others did.[/quote]
Title: Re: Sure Electronics PICkit 3
Post by: MaurizioT on June 20, 2017, 10:27:57 am
I would like to know the Sure schematic.
Inside the ZIP file from their web site is present a PDF file with the Microchip schematic in a unreadable way.
Can be they have done this because the Microchip schematic is different.
At today I haven't found their schematic.
It is not a problem because it is working but can be useful to see if we can improve it.