here is the LD-29 MCU pinout (eg how to put your ATtiny13A in there...)

What version of adapter are you using? Pin4 has no GND however grounding it with tweezers doesnt help…

Ok I know you’ve said you cant be bothered to take / post a few pic’s of your new version driver but can you PLEASE? I didnt test my driver when it came and i’ve got the adapter removed back off it and none of the PIC MCU pad’s are GND! I also notice a empty pad coming from pin8, it sits right next to it and appears to have a diode marking however the other pad of the set goes pin 4 of the to the small 6-pin component marked 8205S right below the MCU, not GND.

I’d really like to get this thing working, I have a project for it but I have so many other project’s on my plate (including all my oersonal projects as well as the 1AA boost driver I’m doing for TFF and a new AVR programmer) that I can do the stuff you figure out but I cant devote any time to actually dive in myself.

edit: good news is driver works with the PIC MCU (had to try a few different ones, I have multiple pulled 12F683’s from different drivers lol), now I’ll just wait to see what you think.
I dont need a pic anymore but could you please post a complete list of each step required to get it running all in one post?

thx

edit2: what resistors are you using to get 5A? I’ve tried every combo of resistors I have and the only thing I can do is decrease power, I wasnt able to get it any over 3A. I’ve tried from adding a second .025 all the way up to 36ohm, I also tried no resistor, just a jumper…

Let’s not get into that. I really do not appreciate any pressure from you to do unnecessary things. I’ve posted pics and markings. All you’ve gotta do is look at them.

Step one for you is to confirm that your driver works as expected without the PIC in place. As I mentioned earlier, the stock firmware never allows 100% duty cycle on the PWM/blanking/toff/whatever input for the buck circuit, so you should see 3.5-4A without doing any resistor mods. So you’ll need to do what I described in the OP:

Once you’ve done that you can move on to trying to install an ATtiny13A. For that, simply follow the explicit details I posted in #56. I haven’t done any work on the LD-29 that I haven’t posted in this thread other than the brief discussion over in the STAR firmware thread about moving PWM outputs, so the status is exactly what you see in #56. I used the v07 adapter boards. Note that after installing the adapter board and before installing the MCU I did test the driver by pulling the Enable and PWM pins high - I wasn’t really 100% sure that the adapter board would reflow the way I expected, but it seems that it did.

Not having GND is OK, don’t worry about it. I’m not sure if shorting MCU GND to BAT- is OK though, so make sure your ATtiny still works. There’s a lot of stuff going on on an LD-29, I haven’t made a circuit diagram and I have no clue how most of it actually works ;-).

The firmware you keep flashing doesn’t work - I mentioned that when I posted it.

Hey guys,

Sorry I couldn’t log in for the last 3 months.
wight, Thanks for your hard work!

I had a little time playing with my ld-29 today.
They are really seems to be a little different from the old ones.

I removed the PIC from the driver, wired it to the LED, and as expected - it didn’t work.

Then I jumpered pin1-pin3 and pin1-pin5 - still didn’t work for me.
I tried playing a little more with the jumpers, and managed to get it work on MAX with jumpers : pin1-pin2 and pin1-pin5.

  • Why could It happen? [on the OP it is still written that pin3 is the pwm]

The strange thing is that it works at about ~4A on the LED on max, which is too high for XM-L’s .

* Is there any way reducing the amp without pwm (without adding an MCU ) ?
EDIT: I could manage to lower the output to exactly 3.0A with a resistor of 0.031058ohm. now it is okay.

Another interesting question, 3 months ago I ordered “PIC to ATTINY v06”

  • will it work with an Attiny? or should I order the v07?

THANKS!! :wink:

Hi again HiTiT, it’s been a while since I did anything with this (all the latest info is in this thread of course). I’ll have to refresh my memory. I’ll remove the PIC from the new-version LD-29 I have ASAP and verify your findings. IIRC when I examined them they seemed very similar. I am surprised by what you experienced.

Where did you place that resistor?

Thanks again for your help!
yep, it is strange, but works, I also managed to put a reed switch and made it work as a momentary switch with a magnet.
I made a jumper between pin1-pin5, and put the reed switch on pin1-pin2, otherwise it didn’t work correctly.

I put everything into my OLD diving light Trustfire TR-J2, and it seems to work great in there - but with no modes - as there is no MCU…

I de-soldered R025 which goes into LED - [ if i’m not mistaken] and soldered a new one there.
I want the light to work @3.3A on LED so I ordered some new precise [1%] resistors to play with.

by the way, I forgot how buck drivers work, if I get 3.0A on LED, how many Amp should I see on tailcap? :slight_smile:

Sorry HiTiT, I probably meant to reply but did not. Glad things seem to be going well.

You will not be able to accurately estimate output current by monitoring only tailcap current. That said, the way I do it is:

  • I assume 80% driver efficiency.
  • To estimate output current:
    A. I multiply input current by input voltage.
    B. I multiply that by the efficiency (0.80).
    C. I divide that by the estimated output voltage, generally derived from a Vf chart such as those generated by Match or djozz. Typically an XM-L2 will be around 3.4-4.2v or something, depending on drive current. Look up djozz’s “crash testing” threads for more info.
  • To estimate input current:
    A. I multiply output current by output voltage (usually I’d use a measured current or I’d estimate the current based on the current sensing resistor).
    B. I divide that by the efficiency (0.80). That means that our working number will increase of course!
    C. I divide that by input voltage.

If I have better efficiency figures for the driver of course I use those instead! Anywhere I can replace estimates, extrapolations, etc with accurate measured values I do.

just for the record
Fasttech are now shipping a new model of ld-29:
Did’t test it yet.

It is still using a PIC MCU, so I hope that wight’s adapter will work.
I am trying to write a firmware on the attiny that will be able to read a Hall effect sensor on it’s analog pin and output the light whenever a magnet is being close to it.

^

Did wight ever fix that Attiny13a/PIC adapter board?

Yep, he tried v6 and it worked with a small modification IIRC
now I’m waiting for v7 to arrive:
https://oshpark.com/shared_projects/iN0zkxJn