[LF686C20] [BL602] Magic Home RGBW 12-24v 5-pin LED Strip Controller
TL;DR
- A Magic Home RGBW 12-24v 5-pin LED strip controller with an LF686 chip flashed as a BL602 is being configured for OpenBeken.
- Flashing succeeded only after soldering all pads, powering BOOT from the external 3.3v rail directly, and using BLDevCube 1.4.8 instead of 1.8.8.
- The working hookup used Ext 3.3v to V33, Ext 3.3v through a 10k resistor to BOOT, GND to GND, and TTL RX/TX crossed to the TX/RX pads.
- Wi‑Fi appeared only with the external DC jack connected, and GPIO Finder showed pin 20 toggling, but the RGBW pinout and OBK template remain uncertain.
AI summary based on the discussion. May contain errors.
Presenting a familiar device, one I've seen around the forum, but this one is without an Ir receiver and comes with an LF686 chip, which is to be flashed as a BL602.
I spent HOURS trying to get this to flash with my pogo pins and several different USB-TTL adaptors but I only got success after soldering all pads AND pulling BOOT from 3.3v rail on external PSU directly, not via V33 pad and 10k resistor. I also tried v 1.8.8 of the BLDevcube. Success was using 1.4.8.
Ext 3.3v -> V33 pad
Ext 3.3v -> 10k R -> BOOT pad
Ext GND -> GND pad
TTL RX -> TX pad
TTL TX -> RX pad
TTL GND -> Ext GND
Post-flash there was no wifi, even using external 3.3v (and with BOOT unsoldered), but with the external DC jack connected, it all came up. I did not use V+ and GND pads on this board. I have read in another thread that someone had success flashing with 5V on V+.
I tried the device profile of this device but cleared the ir GPIO and used the GPIO Finder to see that pin 20 toggled something on/off
Unfortunately the 4 pin RGB strip I used in testing did not have a W pin and the energizer 5-pin RGBW strip I also have didn't seem to match the RGB pinout, so I'm only reasonably confident this is the correct OBK template (should RGB be 0,1,2 and the W 3 or 4 (there's no C)?):
I spent HOURS trying to get this to flash with my pogo pins and several different USB-TTL adaptors but I only got success after soldering all pads AND pulling BOOT from 3.3v rail on external PSU directly, not via V33 pad and 10k resistor. I also tried v 1.8.8 of the BLDevcube. Success was using 1.4.8.
Ext 3.3v -> V33 pad
Ext 3.3v -> 10k R -> BOOT pad
Ext GND -> GND pad
TTL RX -> TX pad
TTL TX -> RX pad
TTL GND -> Ext GND
Post-flash there was no wifi, even using external 3.3v (and with BOOT unsoldered), but with the external DC jack connected, it all came up. I did not use V+ and GND pads on this board. I have read in another thread that someone had success flashing with 5V on V+.
I tried the device profile of this device but cleared the ir GPIO and used the GPIO Finder to see that pin 20 toggled something on/off
Unfortunately the 4 pin RGB strip I used in testing did not have a W pin and the energizer 5-pin RGBW strip I also have didn't seem to match the RGB pinout, so I'm only reasonably confident this is the correct OBK template (should RGB be 0,1,2 and the W 3 or 4 (there's no C)?):
Code: JSON
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Comments
So it's basically the strip controller from out video but with a different marking on the chip? I'm really curious what is the backstory behind LF686C20, is it made by the same company as BL602? [Read more]
Indeed, but without the infrared option on the PCB and 5 pins. Added after 6 [minutes]: Me too. Maybe I'll email Leapfive and ask. [Read more]
Hi there. First of all thank you for all the amazing work already done! I have a dumb question, but i have to ask it. It's about the external power supply. Can I use the USB TTL as said extenral power... [Read more]
a good question. I have had success flashing a couple of smaller devices when I first started, but now I just use an external (NOT the 3.3v from the USB-TTL) wherever I can to save wondering if my fails... [Read more]
I think i get the idea. I was also looking at a board like that for the power supply, but now i am conviced i will get one to mitigate power issues as you mentioned. In the meantime i will try with an... [Read more]
sure. I have used the 12v DC jack from a standard mains PSU with barrel connector (one I found in a drawer with a connector that fits) for flashing some LED strip controllers. I've yet to blow anything.... [Read more]
It is possible to use Arduino or NodeMCU as both USB to UART converter and a power supply, but in order to do that, you need to put ESP (or Atmega) in the RESET state, by shorting RESET to ground. [Read more]
Never liked electricity so i will skip this scenario altogether :D This I like. This is doable. I will try it. Thank you for the input. Edit: It worked like charm. Arduino mega as ext. Psu put... [Read more]
I may forgot to say that earlier, but if you have LF686/BL602 device and consider flashing it, please take a firmware backup first. I am actively looking for BL602 firmware dumps. Just keep it in mind... [Read more]
Did you manage to backup the firmware for the device in this thread? What is the procedure for backing up a BL602? Can we only flash with bldevcube? [Read more]
I don't know much about it, I haven't tried it yet. There is a similiar thread where user used other tool: https://www.elektroda.com/rtvforum/topic4027953.html As far as I know there is also some kind... [Read more]
ah yes. looks like I downloaded that on the 29th December but immediately forgot, then proceeded to flash the device with OpenBL602. I've another Magic Home BL602 untouched. Here is the boot log attached... [Read more]
and here is a dump deleted. was junk https://obrazki.elektroda.pl/2791223000_1705141343_thumb.jpg blflash-windows-amd64.exe dump MagicHome_LED_BL602_LF686.bin 115200 --port COM10 [Read more]
Is it full dump? This device has 2MB flash, right? Hmm. Maybe you need to specify the size. [Read more]
hmm, unsure. during the dump it does give a progress/total bar. 911.50kib is total. I don't see any size option switches for the exe. I'll play more later https://obrazki.elektroda.pl/2889084600_1705142014_thumb.jpg... [Read more]
So can you try to use this command to dump 2MB? https://obrazki.elektroda.pl/5894231900_1705156934_thumb.jpg [Read more]
Here's the 2MB using deleted. was junk blflash-windows-amd64.exe dump 2MB_MagicHome_LED_BL602_LF686.bin 115200 2097152 --port COM10 . No idea if it's complete. [Read more]
Glad you had success @mavrov. What device did you flash, and are the ones you have all the same? [Read more]
I still haven't gotten around to flashing the rest, so I can make a dump of one of those if you still need it. I just need some docs/links on how to do it, but I can make one before flashing. Added after... [Read more]