Quecoo T12-958 soldering station - INVER error?

[redwire]

It's puzzling. I can't tell if it's a hardware or firmware problem. Doubt it's the ground- the mains cord PE goes to the chassis and to the 24V(-)? Other brands float the entire 24VDC side, heater+tip included, which is a disaster for noise and HV potential when running off mains. Just wondering how TC noise could be worse running off a battery, isolated from everything.

[spleenharvester]

Hi all

Long story short I tried to flash CFW and bricked it - turns out this is a brand new T12-958 board design with different pins, and until a few days ago the original firmware dump was unavailable. Myself and someone else over EEVBlog traced the pins and got a relatively complete schematic of the controller, and David kindly released a new CFW for it that I'm told is working. But I accidentally killed my T12-958 in the process of tracing the schematic so that's the end of that!

Quicko have actually released a 'T12-A' station that is designed specifically for Milwaukee/DeWalt/etc batteries recently - I might buy that as it's better suited to what I'm doing anyway, and see if they've done anything different to make it work with tool batteries. Would also be good to see how it compares to the new T12-958 board as it looks like they are possibly the same or very similar.

Cheers

[stj]

there isnt much to kill - fix it

[spleenharvester]

lol I tore the display ribbon and lack the dexterity to replace it. Just less of a pain in the ass to buy a new one.

I finished tracing the board - have attached the schematic if anyone is curious!

[redwire]

I can see a few mistakes in your posted schematic. For alternate firmware like David's you need the I/O pin assignments.
What's interesting is Quicko is also monitoring heater current, this is not done anywhere else.
I've drawn a bunch of detailed KSGER T12 controller schematics. I quit after people took my schematics made a few edits and plastered their name all over it, for fame and glory.

[stj]

monitoring current is good for a cartridge system, dont want to blow a fet because a cartridge isnt fully plugged in!

[spleenharvester]

I can see a few mistakes in your posted schematic. For alternate firmware like David's you need the I/O pin assignments.
What's interesting is Quicko is also monitoring heater current, this is not done anywhere else.
I've drawn a bunch of detailed KSGER T12 controller schematics. I quit after people took my schematics made a few edits and plastered their name all over it, for fame and glory.

Yeah more than likely there are some errors, I have no electrical engineering background so don't really have any idea what I'm tracing. Which bits are wrong as I'll correct them? Have found the RTC missing 3.3V assignment since,


All the connected I/O pins are there, David was able to produce CFW (well not from this one but someone else's which got the same pin assignments as mine). I mostly finished it for fun really!

[redwire]

What version # is written on your controller board?
When I get time, I'll review the schematic and mention what I think needs to be fixed. Like the thermocouple op-amp circuit does not make sense. BOOT0 is just connected to GND.
I forgot I was drawing this schematic for Quicko STM32 Ver3.3 controller last year, it has a different power supply than yours but some basics should be similar, including I/O assignments.

[macklij]

...
What's interesting is Quicko is also monitoring heater current, this is not done anywhere else.

I've just (today) received a Quecoo T12-958 that looks to be this version (3.2 + 3.2S) and am reading this thread with interest. Thanks for the interesting posts. 🙂

I had planned on installing the custom firmware. But if this Quecoo/Quicko is monitoring heater current, does it mean that the custom firmware should be avoided because the stock firmware is better?

[stj]

it's probably monitoring current just to detect if the cartridge is fitted and working

[redwire]

Using the Post #24 schematic, U7 LMV321 is wired as a comparator but values with R6 5mΩ sense resistor and 130mV at pin3, it trips at >26A which does not make sense.
If it was 50mΩ then >2.6A trip seems reasonable? It does look like it only checks if there is heater current above a certain threshold.

Quicko put in the extra hardware to monitor this. I kinda like their controllers better.

[macklij]

Thanks both. So presumably their firmware is making use of this extra hardware, at a minimum to determine if the cartridge is fitted and working. Does the custom firmware determine the cartridge state in a different (perhaps inferior) way?

I'm basically just trying to decide if I should try the custom firmware or not. There is always the risk of bricking the unit or not being able to go back to Quecoo firmware. But I do have an ST-Link that says 'use me' on the box (well I think that's what the Chinese says)!

Thanks again.

[redwire]

I'm not sure which firmware load to use.
If a heater cartridge goes open-circuit, and these T12 clones are notorious for crappy carts/sockets and connections, there are two ways to tell.
Heater current will not be there when the mosfet is on, or the thermocouple voltage will peg when the heater mosfet is off. Good firmware can figure it out. But it is a shortcoming for some people to think outside the box.

[macklij]

And of course, there is no saying if the original 3.2 firmware will figure it out... or the custom one. I think I'll calibrate some tips and see how it goes with the original firmware. If I hate the menu structure then think again.

Thanks

[stj]

yiou dont need STlink to program the chip, a usb to serial convertor with a 5v or 3.3v output to match the mcu voltage will be fine.

[spleenharvester]

Hi all

My board hasn't actually got a version number printed on it at all, but software reports HW revision 3.2. I've fixed the BOOT0 and RTC issues in my schematic (I had BOOT0 connected like that as the traces are physically connected to it, but as someone said on EEVBlog it just seems to be grounded out anyway).


R6 is definitely 5 milliohm, has R005 printed on it. I have rechecked and am also convinced the other resistors are correct in that part of the schematic. I've added a missing 4K7 to ground on V+ but I don't think that makes a difference as it's not on +in or -in?

[macklij]

yiou dont need STlink to program the chip, a usb to serial convertor with a 5v or 3.3v output to match the mcu voltage will be fine.

Thanks. I have both, but have never used the STLink. I don't even know if it works.

[stj]

STlink is a debugging interface that uses the SWIM pin on the mcu - it's a serial jtag interface.
to program with the serial adapter you just use the boot0 jumper/pin and TXD / RXD on the mcu
and this software
https://sourceforge.net/projects/stm32flash/

[spleenharvester]

macklij The board already has header pins to use with an STLink which makes life much easier - just solder a header on and connect any STLink adapter, making sure the station isn't powered up at the same time. The T12 CFW github page has a really good guide on how to use the software.

[macklij]

Thanks both. Yes, I intend to use the STLink with the header pins at some point. I added them when I did the grounding mods for the tip and case (There was already a ground lug on the back panel, but with the case anodising it wasn't being conducted around the case). The ground pin of the 5 pin iron connector wasn't connected to anything either, meaning the soldering iron tip was floating.