CFW for KSGER/Quicko STM32 Soldering Stations

[Cuboy]

Mine is pretty much flat. Sure, that's a simple thing.
Asking that, let me guess... spikes reaching nuclear fission temperatures?

Some spikes. will upload mine once I get my phone working.
Less spiky than the lastest version, so there's that.

Any suggestion to make it flat like yours?

[DavidAlfa]

Make a video, it's hard to guess what's going on.
Remember my tips are already 1 month old, they get better with the use.
What I'm interested now in is comparing another Quicko.
Because that's what annoyes me the most, same hardware, different results.

[Cuboy]

Make a video, it's hard to guess what's going on.
Remember my tips are already 1 month old, they get better with the use.
What I'm interested now in is comparing another Quicko.
Because that's what annoyes me the most, same hardware, different results.

https://streamable.com/upu6s2

Here's the video. Mine is ksger using 3.x

[DavidAlfa]

Looks like a noise issue, but it isn't that bad, that's just 3ºC or so. Worry when you have 50ºC spikes
Could be the voltage regulator, crappy amplifier, who knows.
If your board has the switching 3.3V regulator, I guess it's the best you can get without modding the board.
This is when I say the same thing again: With ksger fw you couldn't see that.
Soldering will work exactly the same with that little noise - it's just that you can see it -
Adding heavier filtering will affect the response and probably make it worse.

If you want to try:

Iron/Filter settings

Filtering: 90%.
Mid limit: 150
Count: 5
Filter: 90%

But as I say, this might drive the PID crazy.

Isn't this a hacking forum? Why I'm not seeing anyone trying adding more caps, showing scope waveforms...?

These ksger don't put a cap in the VDDA pin, neither close to teh amp pins, which is absolute cost-saving crap.
Start by adding 1-10uF ceramic caps there, with 100nF in parallel to improve high frequency response.
Then replace the led with a 1n4148 in direct polarization to gnd, to clamp the voltage to ~0.7V.
That diode is very fast (<4nS) and should help with the spikes.

I would start trying this, hopefully will kill those nasty spikes:

[StephenR0]

So, I flashed today's version on my Quicko.  I did tweak the calibration slightly, but it's pretty close out of the box.  I'm using the default PID settings.  I did play with them some to try to get it more stable, but in the end went back to the defaults.  The displayed temperature fluctuates about 7 or 8 degrees above and below the setpoint.  I'm using 360ºC because that's what everyone seems to be using.  The measured temperature fluctuates in about a 4 to 5 degree range.  This is my BC2 tip, which is my most stable.  Thoughts?

[DavidAlfa]

Make a video if possible!
That's a slow delay, seems caused by a combination of tip + filtering delay
Try reducing "Filtering" in iron settings, maybe to 60%. For me, the noise is marginally higher.
I get some little 1-2ºC spikes below 35-40%.
Test more tips to make sure you didn't take the crappy one

Kd might be doing it worse due the noise, try reducing Kd to 1 or 2 (You too, Cuboy).

Also try different PWM settings, ex. 5ms delay, 50ms pwm.
This is just impossible to get perfect for everyone, each passing day I'm more sure about freezing the temperature screen!

[StephenR0]

I tested all of my tips.  This is with filtering set to 50% and Kd set to 1.  Here are my tips in order, BC2, D24, Ku, C4, and ILS.  I can try to do a video, but I'm not sure what you want to see.  The history of the fluctuation is pretty well described by the graphs.  Do you want to see the actual temperatures as they change?

[StephenR0]

This is just impossible to get perfect for everyone, each passing day I'm more sure about freezing the temperature screen!

I'm not complaining.  I'm sure a fluctuation of 4 or 5 degrees is quite usable.

Edit:  I did try 5ms delay, 50ms pwm (ADC time?).  That didn't change the size of the fluctuations, but things seemed to go faster on the graph screen.

[DavidAlfa]

Yes, it goes faster because it's made like that, updating at the same rate as the pwm/adc for better detail.
Those spikes are really weird. Can you take some pictures of the internals?
Try increasing "mid counter" to 4-5, and "Mid limit" to 150-200.
The "mid" name comes from  previous testing, at first I added more stages (low, mid and high thresholds depending on the noise amplitude), but in the end it didn't provide any improvement, so I removed the high one.
The low noise (Normally used) is just "Filtering".  "Mid filter" is used when the new reading difference is greater than "Mid limit". If the threshold counter keeps rising, and exceeds "Mid counter" , then the filtering will be reduced by -5% everytime as long as it keeps exceeding the limit.
You can also set Mid limit to something very high so it's never used,  ex. 500, and see what happens.
Thats all I can explain for now! I have yet to put proper names there. Or might change everything tomorrow, that's why I didn't bother too much.

Enable debug menu in SYSTEM, it will appear in the main system menu. Enter it and set 360ºC.
Check out AVG (filtered) and RAW (unfiltered), what are the variations?
The ADC setpoint is SET(Converted to adc value), PID tries to reach this value all the time, in perfect conditions AVG and SET would match.

I'm starting to run out of ideas. I can't go further without someone debugging these noisy stations...

[Cuboy]

Looks like a noise issue, but it isn't that bad, that's just 3ºC or so. Worry when you have 50ºC spikes
Could be the voltage regulator, crappy amplifier, who knows.
If your board has the switching 3.3V regulator, I guess it's the best you can get without modding the board.
This is when I say the same thing again: With ksger fw you couldn't see that.
Soldering will work exactly the same with that little noise - it's just that you can see it -
Adding heavier filtering will affect the response and probably make it worse.

If you want to try:

Iron/Filter settings

Filtering: 90%.
Mid limit: 150
Count: 5
Filter: 90%

But as I say, this might drive the PID crazy.

Isn't this a hacking forum? Why I'm not seeing anyone trying adding more caps, showing scope waveforms...?

These ksger don't put a cap in the VDDA pin, neither close to teh amp pins, which is absolute cost-saving crap.
Start by adding 1-10uF ceramic caps there, with 100nF in parallel to improve high frequency response.
Then replace the led with a 1n4148 in direct polarization to gnd, to clamp the voltage to ~0.7V.
That diode is very fast (<4nS) and should help with the spikes.

I would start trying this, hopefully will kill those nasty spikes:

If only I had an oscilloscope... Just for the sake of comparing, I would start playing and adding extra circuitry and seeing how it behaves. This would also be a great learning experience.

For now, I have to stick to what I have and follow what you're saying.

[Acecool]

Does anyone know a socket model number for the STM32 F103 RCT6 - 64 pin, 4x 16 at about 0.25mm spacing...

I've been wanting to do this project for a bit but have a few others going on... so I am thinking of purchasing a few of these chips so that I can desolder the one on my replacement KSGER station, solder the socket on and cut a hole in the top, or side, of the case so it sticks out so that I can swap chips whenever...



Edit: I have board marked OLED-V3.0, in software it reports 3.0 / 3.1 or something along those lines.

I did get pretty lucky with my replacement KSGER - the stm32 chip I have actually has more memory than the original. I do want to see if I can find a way to read the data off the chip, though so I can restore it... but until then I think a socket would be the best bet so I can continue to use it....

If I can't find a inexpensive socket ( some I've seen are around $100 which is crazy ) I could just do a breakout board and then solder the chip to another and just plug the pcb into the breakout and do it that way... It would mean a much larger area for all the pins unless I can see if there is an old cpu socket and cpu I can rip apart and use... that would actually look kind of nifty... But I'd rather have something smaller.


Edit2:

From the previous message by Cuboy quoting a message from DavidAlfa - If you need to know capacitor values, etc... let me know... especially if you have the same board as me... I have a DER DE-5000... I'd probably have to remove the battery - honestly I'd actually be ok with added a header for it... But, it may work without having to undo that... Let me know what readings and what frequency and the position...


Edit 3:

Question: Does anyone know the OLED Model number off my particular KSGER unit? ie: is it color, or just single color? If it is color, I wonder why the colors aren't being used. It would make it much more readable.

[DavidAlfa]

Cheap socket for tqfp64? It's cheaper to buy another Ksger!

[mastershake]

i have a couple of the oled's desoldered i replaced with white panels on the ksger 3.x boards. there is no part number on the screen but i can take some pics or show you which i used to replace them.

these are the white screens i used to replaced the blue ones they are pin for pin and just a teeny big bigger. this may give you the info you need also

https://www.aliexpress.com/item/32903968632.html?spm=a2g0s.9042311.0.0.27424c4daX5ARu

[Acecool]

LQFP-64 Socket is it... There are some for $23 I've found, but that doesn't include the PCB / Mating surface so I'd either have to solder all the wires individually, which would be meh but not the end of the world... there may also be one for $15 on ali...

I could also use a perfboard if the pins on the bottom are spaced ok and find a breakout board and make an adapter... it probably would be cheaper just to buy the kit or just the front part as it would likely be around the same cost... The only benefit of this idea would be the ability to quickly swap in and out chips without having to move any of my setup around, etc...

[ricktendo]

  Another minor feature request, add option to use eeprom for storage of settings/misc.

[wickated]

https://streamable.com/upu6s2

Here's the video. Mine is ksger using 3.x

absolutely stable.

[DavidAlfa]

Another minor feature request, add option to use eeprom for storage of settings/misc.

Not this one, when the whole firmware is already based on the flash, and some boards have it, others doesn't... Why make it more complicated?
Also, these eeproms are 8Kbit, current settings doesn't fit there.
Just why ask for a feature that is not needed neither affecting in any way the station behavior?

absolutely stable.

Was that an irony? It's almost perfect!

[wickated]

Was that an irony? It's almost perfect!

absolutely no irony. best u can get with pwm psu and pwm instead of ldo

[DavidAlfa]

Can you change fast increments to 10º and slow ones to 1º by default? I think that's better than 20º and 10º.

After a day of 1/10 steps, all can I say is that's incredibly annoying.
I'll put 5/20, which lets you use reasonable steps yet moving fast when needed.

I've been suspecting this since the beginning. The tips go worse as they age.
I've tested builds back to February. The all do really bad with my current tips.
They just grow grass like StephenR0's.

These tips are just crap, from the start to the end.
So definitely, will have to just ignore that in the display. I don't see other way.
These tips simply change too much between suppliers and during their lifetime.

[DavidAlfa]

Another full day fighting this 
New filtering, I think now it's easier to understand, also works pretty well.

Diff means: difference between average and new reading

*FILTER SETTINGS*

- Filter: Coefficient of the filter
    - Threshold: Define normal noise level. Diff lower than this will be filter normally. If greater, will increase "threshold  counter"
    - Count limit: If the threshold counter is below this, normal filter will be used. If exceeded, will start reducing the filter coefficient by "Step down", until reaching "Min"
    - Step down: Filter reduction step applied each time
    - Min: Minimum filter coefficient, don't go below this.

- Reset limit: If diff greater than this, filter is resetted (ex. Tip removed)

Now let me explain a practical example:

If the normal tip noise in around 20, you set a bigger threshold to have more clearance, ex. 50. Also, if the tip changes too fast, you might increase it a little more.
Now, the new reading reports +100, could be just noise ,or the temp changing fast. The threshold is triggered and the counter increased.
While the counter is below the limit, it will be filter normally, and barely affect the average. You'll need to adjust this depending on how noisy your signal is.
If the next readings is under the threshold, the counter is cleared, but if not, it keeps increasing.
When that counter exceeds the limit, each time the filter coefficient will be lowered, until reaching the min. set value.

Ex. when heating a cold tip, it'll usually be faster than the filter, so if we have a coefficient=90, step down = -5 , min=50, the filter will do 90%,85,80,75,70,65,60,55,50,50,50... and when the readings get normal again, return to 90%.
Anytime a reading is under the threshold, the filter will be restored and the counter resetted.

The higher the threshold and the count limit, the slowest the filter will react. So this always require a lot of testing.
It's easy to have a clean signal by skyrocketing the filter values, but you'll get a slow oscillation caused by the filter response. Though still better than having it jumping around like crazy.

The noise levels can be seen in the DEBUG menu. Set a normal temp (Ex. 350) and check the values in the field RAW. Your noise is highest-lowest. Add some clearance and start testing.
There's nothing the sw can do to improve the RAW readings, that's how the ADC is reading the signal, it purely depends on the external circuitry.

Edit:
The problem is definitely due the tip sensor. It's impossible that they heat up +100ºC in just 1 second, but the sensor does read that.
Tips having little use work better.
So the PID needs to be very responsive, requiring ver narrow adjustments. Its very easy to over or under compensate, both causing spikes and oscillations.
The fact that the PID is able to control it with only 5Hz sampling rate is already amazing.
Opened a new tip, it jumped for 5-10 seconds and after that it worked great. Don't know if I was just lucky or if it's the current filtering doing great.

Current filtering is set at 95%. Seems to greatly cut down the noise, and the adaptative filtering does the rest.

New builds available!

[Cuboy]

Feedback here:

I can say it has improved drastically from the last video, with much fewer spikes, it's almost perfect.I get some small 1 pixel spikes here and there, maybe 2 or 3 horizontally and that's it 

[DavidAlfa]

Great! I was about to make my station land somewhere in between Germany and Russia!
What about the response?
1 pixel is just 1ºC, can't even be called noise.

[Cuboy]

What response are you referring to?

Everything is by default. I made a reset.

[DavidAlfa]

I mean what happens when plugging a cold tip, or touching the wet sponge.
How does it react? The PID is also different.

[Cuboy]

I mean what happens when plugging a cold tip, or touching the wet sponge.
How does it react? The PID is also different.

It reacts perfectly, temp down while on wet sponge, power to the tip goes up, then stabilizes to its set temp. maybe a little overshoot because of extra power (of 1ºC)

Now I don't get any temperature oscillations, the temperature plot is as flat as it can be.