Hello first time here, I recently bought a rgb light from aliexpress The disassembly was pretty easy and I didn't damage the light thanks to the video from elektroda channel And I was able to access to this: After desoldering the module and seeing that it was a LN882HKI I was able to find the...

Name: [LN882HKI] Tuya Smart Light disassembly and seek some help to set it up
Uploaded: 2024-02-20T12:46:19+01:00
Description: Hello first time here, I recently bought a rgb light from aliexpress The disassembly was pretty easy and I didn't damage the light thanks to the video from elektroda channel And I was able to access to this: After desoldering the module and seeing that it was a LN882HKI I was able to find the...

sounds like you're doing the right thing? I've experienced freezing on some pins before but I just reboot and carry on. Perhaps start from the bottom instead. Added after 10 [minutes]: if they're PWM controlled LEDs, seems like only these pins can be used on LN882H anyway though 8 GPIOA7 I/O PWM pin, corresponding to pin 15 of the IC. 9 GPIOA10 I/O PWM pin, corresponding to pin 21 of the IC. 10 GPIOA11 I/O PWM pin, corresponding to pin 22 of the IC. 11 GPIOA12 I/O PWM pin, corresponding to pin 23 of the IC. 12 GPIOB3 I/O PWM pin, corresponding to pin 24 of the IC.

Ah I see. I'm still quite new to OpenBK. I don't think I've had to set BP5758 channels on any bulbs. I do see there is DAT and CLK for that chip tho, so I guess it's finding the gpios for those two. Perhaps there'd be continuity between two of the contacts on the PCB and two legs of the BP?

my turn to break one of these, but not sure how. I was so careful! UART just outputs junk now and there's no sign it's transmitting. I didn't get to flash it, but before I killed it, these are the pins and boot log. I've ordered another one lol. 😫 Code: text Expand Select all Copy to clipboard bootloader build time: 13:48:19 config item not found perip_param value -- tuya project compile time: Jul 24 2023 10:07:45-- ble mac[8d:57:49:68:d6:d8] BLIB Ver: 1.0.3 [0x010003ff] xTaskCreate, name: rw_task, priority: 9, stack size: 2048 xTaskCreate, name: worker, priority: 2, stack size: 1536 xTaskCreate, name: ty_main, priority: 3, stack size: 4096 xTaskCreate, name: IDLE, priority: 0, stack size: 1024 xTaskCreate, name: Tmr Svc, priority: 10, stack size: 2048 Before enter tuya_main, Total:164292; Free:151952 GPIOA_9 high level, will enter Normal mode! Failed to enter ate mode! Start tuya user main. xTaskCreate, name: tuya_app_main, priority: 4, stack size: 4096 xTaskCreate, name: TUYA_TCPIP, priority: 9, stack size: 2048 tkl_ethernetif_init tkl_ethernetif_init [01-01 00:00:00 ty I][lr:0x100c8f0f] mqc app init ... xTaskCreate, name: wq_system, priority: 3, stack size: 5120 [01-01 00:00:00 ty I][tal_thread.c:184] thread_create name:wq_system,stackDepth:5120,totalstackDepth:7168,priority:3 xTaskCreate, name: wq_highpri, priority: 4, stack size: 4096 [01-01 00:00:00 ty I][tal_thread.c:184] thread_create name:wq_highpri,stackDepth:4096,totalstackDepth:11264,priority:4 xTaskCreate, name: sys_timer, priority: 5, stack s[01-01 00:00:00 ty D][tal_thread.c:203] Thread:wq_highpri Exec Start. Set to Runningize: 4096 Stat [01-01 00:00:00 ty D][tal_thread.c:203] Thread:sys_timer Exec Start. Set to Running Stat [01-01 00:00:00 ty I][tal_thread.c:184] thread_create name:sys_timer,stackDepth:4096,totalstackDepth:15360,priority:5 [01-01 00:00:00 ty E] ===== bp5758d_init ->ucNumber 5 , total_out_index 10 ====== [01-01 00:00:00 ty E][lr:0x100d3d9d] uf_open 8 err 8 [01-01 00:00:00 ty E] uf file 8 can't open and read [01-01 00:00:00 ty E][light_memory.c:102] power mem read err [01-01 00:00:00 ty N][lr:0x10077a13] reset is 0>> xTaskCreate, name: thread_shade, priority: 5, stack size: 2048 [01-01 00:00:00 ty N][lr:0x10088c7f] ble serv not closed, forbid open! [01-01 00:00:00 ty N][lr:0x10077395] BleSwitch=1 [01-01 00:00:00 ty E][lr:0x100d3d9d] uf_open 8 err 8 [01-01 00:00:00 ty E] uf file 8 can't open and read [01-01 00:00:00 ty E][light_memory.c:102] power mem read err [01-01 00:00:00 ty N][lr:0x10077a13] reset is 0>> [01-01 00:00:00 ty N][lr:0x100773b3] first bright up [01-01 00:00:00 ty N][lr:0x10077a13] reset is 0>> [01-01 00:00:00 ty N][lr:0x100bff73] key_addr: 0x1ec000 block_sz 4096 [01-01 00:00:00 ty N][lr:0x100c024d] get key: 0xb7 0xda 0x23 0x52 0x55 0x7b 0xb4 0x8d 0x76 0x81 0x68 0x40 0x81 0x51 0x7e 0xb5 [01-01 00:00:00 ty N][lr:0x10083e19] uni_random_init... [01-01 00:00:00 ty N][lr:0x100840bd] tuya_tls_rand_init ok! ----- tkl_watchdog_init wdg shift_left_num:0x10, set num:65535, top:0x0d xTaskCreate, name: health_monitor, priority: 5, stack size: 1536 [01-01 00:00:00 ty E][lr:0x100c8623] logseq empty tkl_cpu_sleep_mode_set 95 1 0 tkl_cpu_sleep_mode_set 95 0 0 tkl_wifi_set_lp_mode 1566, en 0, dtim 0 [01-01 00:00:00 ty E][tal_wifi.c:714] tal_wifi_lp_dis: set wifi lp mode fail(-26880) [01-01 00:00:00 ty N][lr:0x100ab263] mf is open need stop fastconnect set work mode 1, is open 0, current ln mode: 0 wifi not start, turn on first adapt wifi start , hw_ready:0 start rf preprocess and image cal [WLIB_E]idx=00, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 69, qavg= 63 [WLIB_E]idx=01, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 10, qavg= 26 [WLIB_E]idx=02, iq_hex_cal=0x8079, i=128, q=121, iavg= 74, qavg= 54 [WLIB_E]idx=03, iq_hex_cal=0x8174, i=129, q=116, iavg= 34, qavg= 9 [WLIB_E]idx=04, iq_hex_cal=0x816F, i=129, q=111, iavg= 18, qavg= 48 [WLIB_E]idx=05, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 46, qavg= 54 [WLIB_E]idx=06, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 51, qavg= 7 [WLIB_E]idx=07, iq_hex_cal=0x807A, i=128, q=122, iavg= 10, qavg= 70 [WLIB_E]idx=08, iq_hex_cal=0x8275, i=130, q=117, iavg= 19, qavg= 8 [WLIB_E]idx=09, iq_hex_cal=0x836F, i=131, q=111, iavg= 9, qavg= 38 [WLIB_E]idx=10, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 50, qavg= 54 [WLIB_E]idx=11, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 45, qavg= 10 [WLIB_E]idx=12, iq_hex_cal=0x8079, i=128, q=121, iavg= 25, qavg= 67 [WLIB_E]idx=13, iq_hex_cal=0x8275, i=130, q=117, iavg= 32, qavg= 5 [WLIB_E]idx=14, iq_hex_cal=0x826F, i=130, q=111, iavg= 8, qavg= 32 [WLIB_E]idx=15, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 44, qavg= 58 [WLIB_E]idx=16, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 50, qavg= 20 [WLIB_E]idx=17, iq_hex_cal=0x8179, i=129, q=121, iavg= 1, qavg= 59 [WLIB_E]idx=18, iq_hex_cal=0x8274, i=130, q=116, iavg= 33, qavg= 21 [WLIB_E]idx=19, iq_hex_cal=0x836F, i=131, q=111, iavg= 24, qavg= 36 [WLIB_E]idx=20, iq_hex_cal=0x7D7F, i=125, q=127, iavg= 12, qavg= 1 [WLIB_E]idx=21, iq_hex_cal=0x7D7E, i=125, q=126, iavg= 26, qavg= 46 [WLIB_E]idx=22, iq_hex_cal=0x7D7D, i=125, q=125, iavg= 36, qavg= 25 [WLIB_E]idx=23, iq_hex_cal=0x7D7B, i=125, q=123, iavg= 31, qavg= 21 [WLIB_E]idx=24, iq_hex_cal=0x7C79, i=124, q=121, iavg= 39, qavg= 38 xTaskCreate, name: wifi_cfg, priority: 5, stack size: 2048 xTaskCreate, name: mac_task, priority: 9, stack size: 2048 [WLIB_I]cap_comp = -12, xtal_capbank_tab:[0]:28 [1]:23 [2]:23 [3]:23 [4]:38 [5]:58 [6]:58 [7]:58 [WLIB_I][original]phy_tab_1f:0x56, phy_tab_20:0x3C [WLIB_I][efuse]phy_tab_1f:0x5A, phy_tab_20:0x40 [WLIB_I][flash]phy_tab_1f:0x5A, phy_tab_20:0x2B, tx_pwr_comp_all=0, tx_pwr_comp_b=-21, tx_pwr_comp_gn=0 [WLIB_I]==>temp_sect:2,phy_tab_1f:0x5A,phy_tab_20:0x2B [WLIB_I]gw_wsm.stat:1 [01-01 00:00:02 ty N][lr:0x10099083] gw_cntl->gw_if.abi:0 input:0 [01-01 00:00:02 ty N][lr:0x10099091] gw_cntl->gw_if.product_key:keyh84mvjw3x7qdf, input:keyh84mvjw3x7qdf [01-01 00:00:02 ty N][lr:0x1009909d] gw_cntl->gw_if.tp:0, input:0 [01-01 00:00:02 ty N][lr:0x100990b1] gw_cntl->gw_if.firmware_key:keyh84mvjw3x7qdf, input:keyh84mvjw3x7qdf [01-01 00:00:02 ty N][lr:0x100996b5] enter success_proc [tkl_wifi_get_mac:1229] if: 0, mac: d8:d6:68:49:57:8c ble_mac: 8d:57:49:68:d6:d8 [01-01 00:00:02 ty N][lr:0x100996c9] serial_no:d8d66849578c [01-01 00:00:02 ty N][lr:0x10078933] frame init ok ty N][lr:0x100717eb] opMeshRemoterCtrlInit!urrent ln mode: 0 current work mode 0 [WLIB_I]Disconnected. xTaskCreate, name: remoter_cmd_deal, priority: 3, stack size: 2560 [01-01 00:00:02 ty I][tal_thread.c:184] thread_create name:remoter_cmd_deal,stackDepth:2560,totalstackDepth:28672,priority:3 [01-01 00:00:02 ty N][lr:0x100789a1] ble remote ok [WLIB_I]LN882H WiFi Lib Ver: 1.1.3 [0x010103ff] [WLIB_I]SoftAP_Startup. SoftAP startup! [WLIB_I]HwInd:UKI:0 [WLIB_I]Channel scanning not needed [WLIB_I]User Preferred channel idx 5-0 [WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5 [WLIB_I]Selected Channel Tbl Idx 5-0 [WLIB_I]AP: Starting network in 5-0 [WLIB_I]Connected. [WLIB_I]Status: Start Successful. Entering Enable State. tkl_thread_release, name: tuya_app_ [WLIB_I]Disconnected. [WLIB_I]Channel scanning not needed [WLIB_I]User Preferred channel idx 5-0 [WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5 [WLIB_I]Selected Channel Tbl Idx 5-0 [WLIB_I]AP: Starting network in 5-0 [WLIB_I]Connected. [WLIB_I]Status: Start Successful. Entering Enable State. [tkl_wifi_get_mac:1229] if: 0, mac: d8:d6:68:49:57:8c ble_mac: 8d:57:49:68:d6:d8 [tkl_wifi_get_mac:1229] if: 1, mac: d8:d6:68:49:57:8d ble_mac: 8d:57:49:68:d6:d8 ssid:SmartLife-578C; pwd:; channel:6, ecn:0, max conn:1, hidden:0beacon:100, mac:d8:d6:68:49:57:8d; start:1 [WLIB_I]Disconnected. ip info: ip: 192.168.176.1 gw: 192.168.176.1 netmask: 255.255.255.0 server config: ip: 192.168.176.1 ip start: 192.168.176.2 ip end: 192.168.176.2 port:67 lease:2880 renew:2880 max client:1 [WLIB_I]LN882H WiFi Lib Ver: 1.1.3 [0x010103ff] [WLIB_I]SoftAP_Startup. SoftAP startup! ap_startup_cb 137, wifi softap up ------- dhcp stop ---------- -------DUMP DHCP SERVER_CONFIG---------- server_config.server=192.168.176.1 server_config.port=67 server_config.lease=2880 server_config.renew=2880 server_config.ip_start=192.168.176.2 server_config.ip_end=192.168.176.2 server_config.max=1 -----------------END-------------- IP_POOL: i=0 192.168.176.2 xTaskCreate, name: dhcpd, priority: 4, stack size: 1280 dhcpd_task start... [WLIB_I]HwInd:UKI:0 [WLIB_I]Channel scanning not needed [WLIB_I]User Preferred channel idx 5-0 [WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5 [WLIB_I]Selected Channel Tbl Idx 5-0 [WLIB_I]AP: Starting network in 5-0 [WLIB_I]Connected. [WLIB_I]Status: Start Successful. Entering Enable State. [WLIB_I]Disconnected. [WLIB_I]Channel scanning not needed [WLIB_I]User Preferred channel idx 5-0 [WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5 [WLIB_I]Selected Channel Tbl Idx 5-0 [WLIB_I]AP: Starting network in 5-0 [WLIB_I]Connected. [WLIB_I]Status: Start Successful. Entering Enable State. [01-01 00:00:02 ty N][lr:0x100abaab] cur stat:13 0x10078421 -->> [01-01 00:00:02 ty N][lr:0x100abae5] wifi netstat changed to:13 -->> [01-01 00:00:02 ty N][lr:0x100abafb] report wifi netstat[13] to callback -->> [01-01 00:00:02 ty N][lr:0x10078439] last wifi stat:255, wifi stat 13 [01-01 00:00:02 ty N][lr:0x10078445] size:111032 [01-01 00:00:02 ty N][lr:0x1007859f] start ez & ap auto blink [01-01 00:00:02 ty N][lr:0x100add25] timer stated, short timer:0x0, long timer:0x100adb65 [01-01 00:00:02 ty N][lr:0x100cc67b] bt startup attr:ff [01-01 00:00:02 ty N][lr:0x1008844f] upd product_id type:1 keyh84mvjw3x7qdf xTaskCreate, name: host_main_thread_hdl, priority: 8, stack size: 5120 [01-01 00:00:02 ty I][tal_thread.c:184] thread_create name:host_main_thread_hdl,stackDepth:5120,totalstackDepth:33792,priority:8 [01-01 00:00:02 ty I][lr:0x100bb15d] le acl buf sz = 251,max buf = 5 [01-01 00:00:02 ty I][lr:0x100b9b7b] acl buf sz = 251, max pkt = 5, avail pkt = 5 [01-01 00:00:02 ty I][lr:0x100bb625] GAP init: stop adv [01-01 00:00:02 ty I][lr:0x1007e775] ble_hs_timer reset:100 [01-01 00:00:02 ty I][lr:0x10080ed9] Stack sync [01-01 00:00:02 ty I][lr:0x10080eb9] Init/Deinit Event [01-01 00:00:02 ty N][lr:0x10088411] ty bt sdk init success finish [01-01 00:00:02 ty N][lr:0x100bbb4b] Start Adv [01-01 00:00:02 ty N][lr:0x100999c7] __devos_init_evt success [01-01 00:00:02 ty I][lr:0x100bb625] GAP init: stop adv [01-01 00:00:02 ty I][lr:0x1007e775] ble_hs_timer reset:0 [01-01 00:00:02 ty N][lr:0x100bbb4b] Start Adv [01-01 00:00:02 ty N][lr:0x10087fc1] ble adv updated xTaskCreate, name: TCP_ap_v4, priority: 5, stack size: 3584 [01-01 00:00:02 ty I][tal_thread.c:184] thread_create name:TCP_ap_v4,stackDepth:3584,totalstackDepth:37376,priority:5 [tkl_wifi_get_mac:1229] if: 0, mac: d8:d6:68:49:57:8c ble_mac: 8d:57:49:68:d6:d8 [tkl_wifi_get_mac:1229] if: 1, mac: d8:d6:68:49:57:8d ble_mac: 8d:57:49:68:d6:d8 [01-01 00:00:02 ty E][lr:0x100a93c1] timer is not run,wait [01-01 00:00:02 ty I][lr:0x1007e879] ble_hs_timer_exp: reboot type(0:power-on;1:soft-rst;2:wdt-rst): 0 reboot count: 0 [ln_ty_sdk_ver: 0.0.5_alpha or 0x00000500] [Git info: develop_198ece8] and some more random pics of the PCB pinched from the Daybetter thread the adventure continues...

Template for this device is Code: JSONLog in, to see the code PR for device list I've made this for the BP5758 driver but I expect it's wrong

Well i tried every gpio except p13 and p14 as it freezes and the leds didn't turn on (to be sure that i was doing good I tried with another rgb light). So to see if the problem is on my side, I checked the soldered points I did but still didn't see a thing and saw that on the leds pcb there was a bp5758 if it can be of any use

You are the first one to find a LN882H + BP5758 combo. I will need to enable BP5758 driver for you. Still, first you need to get a multimeter and check which LN882H pins are used for BP5758 SCL and SDA (or CLK and DAT, it's the same...). This is currently necessary, because there are too many options to just guess. Do you know BP5758 pinout? Are SDA and SCL marked on board?

as you can see SDA and SCL are both marked on the PCB and I think this is the pinout of the BL5758 (as the other pins are all connected to LEDs) And I just wanted to add that for me the pin used by the module are A0 and A1 as the others connected are VCC, GND, and ANT, respectively.

We need to know exactly which pin is SCL and which is SDA.

I should've asked how to proceed with the multimeter because now I think that my device is dead. I first had the cold white light up then with the next pin I had a little electric flash and now nothing except some burn marks on some components.

oh crap! was it not in continuity mode? usually denoted by a beep audio symbol. my meter only has the beep symbol the bulb does not need to be powered when checking for continuity Added after 53 :not that it's any help, but I've ordered one too to play with

Wait, @gregmarfaing , did you do a continuity test on a live device? Everything should be disconnected from mains first. Or, please provide more information on what happened.

Well it's exactly that, I tried with the multimeter while it was powered on (I found this pretty dangerous so I was extra cautious) because it's my time doing this, I'm learning from scratch and I didn't know I had to use the continuous mode while the device was off. Still I really appreciate your help and divadiow's as well. Anyway, I think that I'll buy another one too as it's just so cheap (bought it at 2,69€) i can just add that A0 is connected to SCL and A1 is connected to SDA ( tested with the multimeter in good condition this time with the dead device)

Aww... this sucks! And it's really weird that it broke as the flashing part was really straightforward for me and the module worked flawlessly before breaking it myself.Still, good luck with the next one! I'll buy a new one soon as (I don't know if it's the same in other countries) these cheap things are always on sale at the beginning of the month at AliExpress

yeh annoying. maybe I killed something testing continuity right through to each pin on the IC. no matter, theyre cheap and another will be here in 5 days. Can't be too precious about these cheapo things. Can't say I'd noticed them being cheaper at the beginning of the month really.

[LN882HKI] Tuya Smart Light disassembly and seek some help to set it up

gregmarfaing 12438 79

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How do I configure this LN882HKI Tuya RGB light in OpenBK after flashing it, especially with the BP5758 LED driver?

You need to configure the BP5758 LED driver, not just hunt random GPIOs: the module is an LN882H + BP5758 combo, so first identify which LN882H pins go to the BP5758 SCL/SDA (same as CLK/DAT) with a multimeter rather than guessing [#20970790] The thread later confirmed on this board that A0 is connected to SCL and A1 to SDA [#20971840] Once the driver support was enabled, the working LED mapping was `LED_Map 3 4 2 0 1` [#21010588] For brightness/current, the BP5758 current command was also used to tame heat; `BP5758D_Current 2 2` was reported stable for 2 hours at about 80°C, and `BP5758D_Current 1 1` was said to keep one unit around 73°C [#21011100] [#21650555]

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#1 20970052 20 Feb 2024 12:46

gregmarfaing gregmarfaing

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20970052 20 Feb 2024 12:46

Hello first time here,
I recently bought a rgb light from aliexpress

The disassembly was pretty easy and I didn't damage the light thanks to the video from elektroda channel

And I was able to access to this:

After desoldering the module and seeing that it was a LN882HKI I was able to find the pinout with this topic
I did a backup of the chip and tried to flash obk at 2000000 but after 3 fails I tried at 115200 and it worked right away.
But now I'm facing an issue: I don't know how to setup the module in obk, I tried with the gpio finder but it did nothing except freezing starting P13 so I stopped messing with it.
Thanks in advance for your help and sorry for the typos here and there

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#2 20970107 20 Feb 2024 13:54

divadiow divadiow

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20970107 20 Feb 2024 13:54

gregmarfaing wrote:
i don't know how to setup the module in obk , i tried with the gpio finder but it did nothing except freezing starting P13 so i stopped messing with it .

sounds like you're doing the right thing? I've experienced freezing on some pins before but I just reboot and carry on. Perhaps start from the bottom instead.

https://www.elektroda.com/rtvforum/topic3976371.html

Added after 10 [minutes]:

if they're PWM controlled LEDs, seems like only these pins can be used on LN882H anyway though

8 GPIOA7 I/O PWM pin, corresponding to pin 15 of the IC.
9 GPIOA10 I/O PWM pin, corresponding to pin 21 of the IC.
10 GPIOA11 I/O PWM pin, corresponding to pin 22 of the IC.
11 GPIOA12 I/O PWM pin, corresponding to pin 23 of the IC.
12 GPIOB3 I/O PWM pin, corresponding to pin 24 of the IC.
#3 20970561 20 Feb 2024 18:37

gregmarfaing gregmarfaing

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20970561 20 Feb 2024 18:37

Well i tried every gpio except p13 and p14 as it freezes and the leds didn't turn on (to be sure that i was doing good I tried with another rgb light).
So to see if the problem is on my side, I checked the soldered points I did but still didn't see a thing and saw that on the leds pcb there was a bp5758 if it can be of any use
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#4 20970624 20 Feb 2024 19:06

divadiow divadiow

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20970624 20 Feb 2024 19:06

Ah I see. I'm still quite new to OpenBK. I don't think I've had to set BP5758 channels on any bulbs. I do see there is DAT and CLK for that chip tho, so I guess it's finding the gpios for those two.

Perhaps there'd be continuity between two of the contacts on the PCB and two legs of the BP?
#5 20970790 20 Feb 2024 20:20

p.kaczmarek2 p.kaczmarek2

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20970790 20 Feb 2024 20:20

You are the first one to find a LN882H + BP5758 combo. I will need to enable BP5758 driver for you.

Still, first you need to get a multimeter and check which LN882H pins are used for BP5758 SCL and SDA (or CLK and DAT, it's the same...). This is currently necessary, because there are too many options to just guess.

Do you know BP5758 pinout? Are SDA and SCL marked on board?

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
https://github.com/openshwprojects/OpenBK7231T
If you like my work, support me at: https://paypal.me/openshwprojects

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#6 20970849 20 Feb 2024 20:50

gregmarfaing gregmarfaing

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20970849 20 Feb 2024 20:50

as you can see SDA and SCL are both marked on the PCB and I think this is the pinout of the BL5758 (as the other pins are all connected to LEDs)
And I just wanted to add that for me the pin used by the module are A0 and A1 as the others connected are VCC, GND, and ANT, respectively.
#7 20971149 20 Feb 2024 23:02

p.kaczmarek2 p.kaczmarek2

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20971149 20 Feb 2024 23:02

We need to know exactly which pin is SCL and which is SDA.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
https://github.com/openshwprojects/OpenBK7231T
If you like my work, support me at: https://paypal.me/openshwprojects

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#8 20971544 21 Feb 2024 10:10

gregmarfaing gregmarfaing

Level 7

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Post #8
20971544 21 Feb 2024 10:10

I should've asked how to proceed with the multimeter because now I think that my device is dead. I first had the cold white light up then with the next pin I had a little electric flash and now nothing except some burn marks on some components.
#9 20971601 21 Feb 2024 10:49

divadiow divadiow

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Post #9
20971601 21 Feb 2024 10:49

oh crap!

was it not in continuity mode? usually denoted by a "beep" audio symbol. my meter only has the beep symbol

the bulb does not need to be powered when checking for continuity

Added after 53 [seconds]:

not that it's any help, but I've ordered one too to play with
#10 20971708 21 Feb 2024 12:16

p.kaczmarek2 p.kaczmarek2

Moderator Smart Home

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Post #10
20971708 21 Feb 2024 12:16

Wait, @gregmarfaing , did you do a continuity test on a live device? Everything should be disconnected from mains first. Or, please provide more information on what happened.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
https://github.com/openshwprojects/OpenBK7231T
If you like my work, support me at: https://paypal.me/openshwprojects

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#11 20971840 21 Feb 2024 13:43

gregmarfaing gregmarfaing

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Post #11
20971840 21 Feb 2024 13:43

Well it's exactly that, I tried with the multimeter while it was powered on (I found this pretty dangerous so I was extra cautious) because it's my time doing this, I'm learning from scratch and I didn't know I had to use the continuous mode while the device was off. Still I really appreciate your help and divadiow's as well. Anyway, I think that I'll buy another one too as it's just so cheap (bought it at 2,69€)
i can just add that A0 is connected to SCL and A1 is connected to SDA ( tested with the multimeter in good condition this time with the dead device)

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#12 20983813 29 Feb 2024 09:33

divadiow divadiow

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Post #12

20983813 29 Feb 2024 09:33

my turn to break one of these, but not sure how. I was so careful! UART just outputs junk now and there's no sign it's transmitting.

I didn't get to flash it, but before I killed it, these are the pins and boot log. I've ordered another one lol. 😫


bootloader build time: 13:48:19
config item not found perip_param value
-- tuya project compile time: Jul 24 2023 10:07:45--
ble mac[8d:57:49:68:d6:d8]
[BLIB_I]BLIB Ver: 1.0.3 [build time:Jan 19 2023 12:14:45][0x010003ff]
xTaskCreate, name: rw_task, priority: 9, stack size: 2048
xTaskCreate, name: worker, priority: 2, stack size: 1536
xTaskCreate, name: ty_main, priority: 3, stack size: 4096
xTaskCreate, name: IDLE, priority: 0, stack size: 1024
xTaskCreate, name: Tmr Svc, priority: 10, stack size: 2048
Before enter tuya_main, Total:164292; Free:151952
GPIOA_9 high level, will enter Normal mode!
Failed to enter ate mode! Start tuya user main.
xTaskCreate, name: tuya_app_main, priority: 4, stack size: 4096
xTaskCreate, name: TUYA_TCPIP, priority: 9, stack size: 2048
tkl_ethernetif_init
tkl_ethernetif_init
[01-01 00:00:00 ty I][lr:0x100c8f0f] mqc app init ...
xTaskCreate, name: wq_system, priority: 3, stack size: 5120
[01-01 00:00:00 ty I][tal_thread.c:184] thread_create name:wq_system,stackDepth:5120,totalstackDepth:7168,priority:3
xTaskCreate, name: wq_highpri, priority: 4, stack size: 4096
[01-01 00:00:00 ty I][tal_thread.c:184] thread_create name:wq_highpri,stackDepth:4096,totalstackDepth:11264,priority:4
xTaskCreate, name: sys_timer, priority: 5, stack s[01-01 00:00:00 ty D][tal_thread.c:203] Thread:wq_highpri Exec Start. Set to Runningize: 4096
 Stat
[01-01 00:00:00 ty D][tal_thread.c:203] Thread:sys_timer Exec Start. Set to Running Stat
[01-01 00:00:00 ty I][tal_thread.c:184] thread_create name:sys_timer,stackDepth:4096,totalstackDepth:15360,priority:5
[01-01 00:00:00 ty E][bp5758d.c:263] ===== bp5758d_init ->ucNumber 5 , total_out_index 10 ======

[01-01 00:00:00 ty E][lr:0x100d3d9d] uf_open 8 err 8
[01-01 00:00:00 ty E][soc_flash.c:77] uf file 8 can't open and read
[01-01 00:00:00 ty E][light_memory.c:102] power mem read err
[01-01 00:00:00 ty N][lr:0x10077a13] reset is 0>>
xTaskCreate, name: thread_shade, priority: 5, stack size: 2048
[01-01 00:00:00 ty N][lr:0x10088c7f] ble serv not closed, forbid open!
[01-01 00:00:00 ty N][lr:0x10077395] BleSwitch=1
[01-01 00:00:00 ty E][lr:0x100d3d9d] uf_open 8 err 8
[01-01 00:00:00 ty E][soc_flash.c:77] uf file 8 can't open and read
[01-01 00:00:00 ty E][light_memory.c:102] power mem read err
[01-01 00:00:00 ty N][lr:0x10077a13] reset is 0>>
[01-01 00:00:00 ty N][lr:0x100773b3] first bright up
[01-01 00:00:00 ty N][lr:0x10077a13] reset is 0>>
[01-01 00:00:00 ty N][lr:0x100bff73] key_addr: 0x1ec000   block_sz 4096
[01-01 00:00:00 ty N][lr:0x100c024d] get key:
0xb7 0xda 0x23 0x52 0x55 0x7b 0xb4 0x8d 0x76 0x81 0x68 0x40 0x81 0x51 0x7e 0xb5
[01-01 00:00:00 ty N][lr:0x10083e19] uni_random_init...
[01-01 00:00:00 ty N][lr:0x100840bd] tuya_tls_rand_init ok!
----- tkl_watchdog_init
wdg shift_left_num:0x10, set num:65535, top:0x0d
xTaskCreate, name: health_monitor, priority: 5, stack size: 1536
[01-01 00:00:00 ty E][lr:0x100c8623] logseq empty
tkl_cpu_sleep_mode_set 95 1 0
tkl_cpu_sleep_mode_set 95 0 0
tkl_wifi_set_lp_mode 1566, en 0, dtim 0
[01-01 00:00:00 ty E][tal_wifi.c:714] tal_wifi_lp_dis: set wifi lp mode fail(-26880)
[01-01 00:00:00 ty N][lr:0x100ab263] mf is open need stop fastconnect
set work mode 1, is open 0, current ln mode: 0
wifi not start, turn on first
adapt wifi start <m:1>, hw_ready:0
start rf preprocess and image cal
[WLIB_E]idx=00, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 69, qavg= 63
[WLIB_E]idx=01, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 10, qavg= 26
[WLIB_E]idx=02, iq_hex_cal=0x8079, i=128, q=121, iavg= 74, qavg= 54
[WLIB_E]idx=03, iq_hex_cal=0x8174, i=129, q=116, iavg= 34, qavg=  9
[WLIB_E]idx=04, iq_hex_cal=0x816F, i=129, q=111, iavg= 18, qavg= 48
[WLIB_E]idx=05, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 46, qavg= 54
[WLIB_E]idx=06, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 51, qavg=  7
[WLIB_E]idx=07, iq_hex_cal=0x807A, i=128, q=122, iavg= 10, qavg= 70
[WLIB_E]idx=08, iq_hex_cal=0x8275, i=130, q=117, iavg= 19, qavg=  8
[WLIB_E]idx=09, iq_hex_cal=0x836F, i=131, q=111, iavg=  9, qavg= 38
[WLIB_E]idx=10, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 50, qavg= 54
[WLIB_E]idx=11, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 45, qavg= 10
[WLIB_E]idx=12, iq_hex_cal=0x8079, i=128, q=121, iavg= 25, qavg= 67
[WLIB_E]idx=13, iq_hex_cal=0x8275, i=130, q=117, iavg= 32, qavg=  5
[WLIB_E]idx=14, iq_hex_cal=0x826F, i=130, q=111, iavg=  8, qavg= 32
[WLIB_E]idx=15, iq_hex_cal=0x7E7E, i=126, q=126, iavg= 44, qavg= 58
[WLIB_E]idx=16, iq_hex_cal=0x7F7C, i=127, q=124, iavg= 50, qavg= 20
[WLIB_E]idx=17, iq_hex_cal=0x8179, i=129, q=121, iavg=  1, qavg= 59
[WLIB_E]idx=18, iq_hex_cal=0x8274, i=130, q=116, iavg= 33, qavg= 21
[WLIB_E]idx=19, iq_hex_cal=0x836F, i=131, q=111, iavg= 24, qavg= 36
[WLIB_E]idx=20, iq_hex_cal=0x7D7F, i=125, q=127, iavg= 12, qavg=  1
[WLIB_E]idx=21, iq_hex_cal=0x7D7E, i=125, q=126, iavg= 26, qavg= 46
[WLIB_E]idx=22, iq_hex_cal=0x7D7D, i=125, q=125, iavg= 36, qavg= 25
[WLIB_E]idx=23, iq_hex_cal=0x7D7B, i=125, q=123, iavg= 31, qavg= 21
[WLIB_E]idx=24, iq_hex_cal=0x7C79, i=124, q=121, iavg= 39, qavg= 38
xTaskCreate, name: wifi_cfg, priority: 5, stack size: 2048
xTaskCreate, name: mac_task, priority: 9, stack size: 2048
[WLIB_I]cap_comp = -12, xtal_capbank_tab:[0]:28 [1]:23 [2]:23 [3]:23 [4]:38 [5]:58 [6]:58 [7]:58
[WLIB_I][original]phy_tab_1f:0x56, phy_tab_20:0x3C
[WLIB_I][efuse]phy_tab_1f:0x5A, phy_tab_20:0x40
[WLIB_I][flash]phy_tab_1f:0x5A, phy_tab_20:0x2B, tx_pwr_comp_all=0, tx_pwr_comp_b=-21, tx_pwr_comp_gn=0
[WLIB_I]==>temp_sect:2,phy_tab_1f:0x5A,phy_tab_20:0x2B
[WLIB_I]<==temp_sect:2,phy_tab_1f:0x5A,phy_tab_20:0x2B
XTAL CAP VAL:-12.
wifi stop
wifi sta start
[WLIB_I]LN882H WiFi Lib Ver: 1.1.3 [build time:Apr 24 2023 15:10:58][0x010103ff]
[WLIB_I]STA_Startup.
STA startup!
[WLIB_I]Disconnected.
[WLIB_I]HwInd:UKI:0
[WLIB_I]Disconnected.
current work mode 0
No need to switch mode, mode:0
xTaskCreate, name: mf_test, priority: 4, stack size: 5120
adapt wifi start <m:2>, hw_ready:1
[01-01 00:00:01 ty N][lr:0x1006bbd5] mf_init succ
[01-01 00:00:01 ty N][lr:0x100786f5] < TuyaOS V:3.5.4 BS:40.00_PT:2.3_LAN:3.5_CAD:1.0.5_CD:1.0.0 >
< BUILD AT:2023_01_09_16_12_01 BY ci_manage FOR tuyaos-iot AT ln882h >
IOT DEFS < WIFI_GW:1 DEBUG:1 KV_FILE:0 LITTLE_END:1 SL:0 OPERATING_SYSTEM:98 RELIABLE_TRANSFER:0 >

[01-01 00:00:01 ty N][lr:0x100786ff] w57tepkyqlsegcov_LN882H:1.0.0
[01-01 00:00:01 ty N][lr:0x100787c7] connect mode is 5
tkl_thread_release, name: mf_test
[01-01 00:00:01 ty E][lr:0x100d3d9d] uf_open 2 err 8
[01-01 00:00:01 ty E][soc_flash.c:77] uf file 2 can't open and read
[01-01 00:00:01 ty E][user_flash.c:211] Prod data read err
[01-01 00:00:01 ty E][lr:0x100d3d9d] uf_open 2 err 8
[01-01 00:00:01 ty E][soc_flash.c:77] uf file 2 can't open and read
[01-01 00:00:01 ty E][user_flash.c:211] Prod data read err
[01-01 00:00:01 ty N][lr:0x1006bbf9] prodtest find ssid: tuya_mdev_test1
set work mode 1, is open 1, current ln mode: 0
current work mode 0
No need to switch mode, mode:0
adapt wifi start <m:2>, hw_ready:1
adapt wifi start <m:2>, hw_ready:1
[01-01 00:00:02 ty N][lr:0x100a76c3] wifi soc init. pid:keyh84mvjw3x7qdf firmwarekey:keyh84mvjw3x7qdf ver:1.0.0
[01-01 00:00:02 ty N][lr:0x100aae05] start wifi link params validate, nc_tp:1 md:0
[01-01 00:00:02 ty N][lr:0x100aae8d] gw_wsm.nc_tp:1
[01-01 00:00:02 ty N][lr:0x100aae97] gw_wsm.md:0
[01-01 00:00:02 ty N][lr:0x10098f59] Last reset reason: 0
[01-01 00:00:02 ty N][lr:0x10098fe9] gw_cntl->gw_wsm.stat:1
[01-01 00:00:02 ty N][lr:0x10099083] gw_cntl->gw_if.abi:0 input:0
[01-01 00:00:02 ty N][lr:0x10099091] gw_cntl->gw_if.product_key:keyh84mvjw3x7qdf, input:keyh84mvjw3x7qdf
[01-01 00:00:02 ty N][lr:0x1009909d] gw_cntl->gw_if.tp:0, input:0
[01-01 00:00:02 ty N][lr:0x100990b1] gw_cntl->gw_if.firmware_key:keyh84mvjw3x7qdf, input:keyh84mvjw3x7qdf
[01-01 00:00:02 ty N][lr:0x100996b5] enter success_proc
[tkl_wifi_get_mac:1229] if: 0, mac: d8:d6:68:49:57:8c
ble_mac: 8d:57:49:68:d6:d8
[01-01 00:00:02 ty N][lr:0x100996c9] serial_no:d8d66849578c
[01-01 00:00:02 ty N][lr:0x10078933] frame init ok
 ty N][lr:0x100717eb] opMeshRemoterCtrlInit!urrent ln mode: 0

current work mode 0
[WLIB_I]Disconnected.
xTaskCreate, name: remoter_cmd_deal, priority: 3, stack size: 2560
[01-01 00:00:02 ty I][tal_thread.c:184] thread_create name:remoter_cmd_deal,stackDepth:2560,totalstackDepth:28672,priority:3
[01-01 00:00:02 ty N][lr:0x100789a1] ble remote ok
[WLIB_I]LN882H WiFi Lib Ver: 1.1.3 [build time:Apr 24 2023 15:10:58][0x010103ff]
[WLIB_I]SoftAP_Startup.
SoftAP startup!
[WLIB_I]HwInd:UKI:0
[WLIB_I]Channel scanning not needed
[WLIB_I]User Preferred channel idx 5-0
[WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5
[WLIB_I]Selected Channel Tbl Idx 5-0
[WLIB_I]AP: Starting network in 5-0
[WLIB_I]Connected.
[WLIB_I]Status: Start Successful. Entering Enable State.
tkl_thread_release, name: tuya_app_
[WLIB_I]Disconnected.
[WLIB_I]Channel scanning not needed
[WLIB_I]User Preferred channel idx 5-0
[WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5
[WLIB_I]Selected Channel Tbl Idx 5-0
[WLIB_I]AP: Starting network in 5-0
[WLIB_I]Connected.
[WLIB_I]Status: Start Successful. Entering Enable State.
[tkl_wifi_get_mac:1229] if: 0, mac: d8:d6:68:49:57:8c
ble_mac: 8d:57:49:68:d6:d8
[tkl_wifi_get_mac:1229] if: 1, mac: d8:d6:68:49:57:8d
ble_mac: 8d:57:49:68:d6:d8
ssid:SmartLife-578C; pwd:; channel:6, ecn:0, max conn:1, hidden:0beacon:100, mac:d8:d6:68:49:57:8d; start:1
[WLIB_I]Disconnected.
ip info:
        ip:      192.168.176.1
        gw:      192.168.176.1
        netmask: 255.255.255.0
server config:
        ip:       192.168.176.1
        ip start: 192.168.176.2
        ip end:   192.168.176.2
port:67
lease:2880
renew:2880
max client:1
[WLIB_I]LN882H WiFi Lib Ver: 1.1.3 [build time:Apr 24 2023 15:10:58][0x010103ff]
[WLIB_I]SoftAP_Startup.
SoftAP startup!
ap_startup_cb 137, wifi softap up
------- dhcp stop ----------
-------DUMP DHCP SERVER_CONFIG----------
server_config.server=192.168.176.1
server_config.port=67
server_config.lease=2880
server_config.renew=2880
server_config.ip_start=192.168.176.2
server_config.ip_end=192.168.176.2
server_config.max=1
-----------------END--------------
IP_POOL: i=0 192.168.176.2
xTaskCreate, name: dhcpd, priority: 4, stack size: 1280
dhcpd_task start...
[WLIB_I]HwInd:UKI:0
[WLIB_I]Channel scanning not needed
[WLIB_I]User Preferred channel idx 5-0
[WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5
[WLIB_I]Selected Channel Tbl Idx 5-0
[WLIB_I]AP: Starting network in 5-0
[WLIB_I]Connected.
[WLIB_I]Status: Start Successful. Entering Enable State.
[WLIB_I]Disconnected.
[WLIB_I]Channel scanning not needed
[WLIB_I]User Preferred channel idx 5-0
[WLIB_I]Selecting 20MHz ch from One of ... 0 1 2 3 4 5
[WLIB_I]Selected Channel Tbl Idx 5-0
[WLIB_I]AP: Starting network in 5-0
[WLIB_I]Connected.
[WLIB_I]Status: Start Successful. Entering Enable State.
[01-01 00:00:02 ty N][lr:0x100abaab] cur stat:13  0x10078421 -->>
[01-01 00:00:02 ty N][lr:0x100abae5] wifi netstat changed to:13  -->>
[01-01 00:00:02 ty N][lr:0x100abafb] report wifi netstat[13] to callback  -->>
[01-01 00:00:02 ty N][lr:0x10078439] last wifi stat:255, wifi stat 13
[01-01 00:00:02 ty N][lr:0x10078445] size:111032
[01-01 00:00:02 ty N][lr:0x1007859f] start ez & ap auto blink
[01-01 00:00:02 ty N][lr:0x100add25] timer stated, short timer:0x0, long timer:0x100adb65
[01-01 00:00:02 ty N][lr:0x100cc67b] bt startup attr:ff
[01-01 00:00:02 ty N][lr:0x1008844f] upd product_id type:1 keyh84mvjw3x7qdf
xTaskCreate, name: host_main_thread_hdl, priority: 8, stack size: 5120
[01-01 00:00:02 ty I][tal_thread.c:184] thread_create name:host_main_thread_hdl,stackDepth:5120,totalstackDepth:33792,priority:8
[01-01 00:00:02 ty I][lr:0x100bb15d] le acl buf sz = 251,max buf = 5

[01-01 00:00:02 ty I][lr:0x100b9b7b] acl buf sz = 251, max pkt = 5, avail pkt = 5

[01-01 00:00:02 ty I][lr:0x100bb625] GAP init: stop adv
[01-01 00:00:02 ty I][lr:0x1007e775] ble_hs_timer reset:100
[01-01 00:00:02 ty I][lr:0x10080ed9] Stack sync
[01-01 00:00:02 ty I][lr:0x10080eb9] Init/Deinit Event
[01-01 00:00:02 ty N][lr:0x10088411] ty bt sdk init success finish
[01-01 00:00:02 ty N][lr:0x100bbb4b] Start Adv
[01-01 00:00:02 ty N][lr:0x100999c7] __devos_init_evt success
[01-01 00:00:02 ty I][lr:0x100bb625] GAP init: stop adv
[01-01 00:00:02 ty I][lr:0x1007e775] ble_hs_timer reset:0
[01-01 00:00:02 ty N][lr:0x100bbb4b] Start Adv
[01-01 00:00:02 ty N][lr:0x10087fc1] ble adv updated
xTaskCreate, name: TCP_ap_v4, priority: 5, stack size: 3584
[01-01 00:00:02 ty I][tal_thread.c:184] thread_create name:TCP_ap_v4,stackDepth:3584,totalstackDepth:37376,priority:5
[tkl_wifi_get_mac:1229] if: 0, mac: d8:d6:68:49:57:8c
ble_mac: 8d:57:49:68:d6:d8
[tkl_wifi_get_mac:1229] if: 1, mac: d8:d6:68:49:57:8d
ble_mac: 8d:57:49:68:d6:d8
[01-01 00:00:02 ty E][lr:0x100a93c1] timer is not run,wait
[01-01 00:00:02 ty I][lr:0x1007e879] ble_hs_timer_exp:
reboot type(0:power-on;1:soft-rst;2:wdt-rst): 0
reboot count: 0
[ln_ty_sdk_ver: 0.0.5_alpha or 0x00000500] [build time:2022-05-17_14:57:03]
[Git info: develop_198ece8]
[BLIB Ver: 1.0.3 or 0x010003ff] [build time:Jan 19 2023 12:14:45]

and some more random pics of the PCB

pinched from the Daybetter thread https://www.elektroda.com/rtvforum/topic3925050.html

the adventure continues...

#13 20984119 29 Feb 2024 13:08

gregmarfaing gregmarfaing

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Post #13
20984119 29 Feb 2024 13:08

Aww... this sucks!
And it's really weird that it broke as the flashing part was really straightforward for me and the module worked flawlessly before breaking it myself.
Still, good luck with the next one! I'll buy a new one soon as (I don't know if it's the same in other countries) these cheap things are always on sale at the beginning of the month at AliExpress
#14 20984227 29 Feb 2024 14:04

divadiow divadiow

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Post #14
20984227 29 Feb 2024 14:04

yeh annoying. maybe I killed something testing continuity right through to each pin on the IC. no matter, theyre cheap and another will be here in 5 days. Can't be too precious about these cheapo things.

Can't say I'd noticed them being cheaper at the beginning of the month really.
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#15 20994908 07 Mar 2024 21:51

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Post #15
20994908 07 Mar 2024 21:51

Template for this device is

Code: JSON
Log in, to see the code

PR for device list https://github.com/OpenBekenIOT/webapp/pull/83

I've made this for the BP5758 driver but I expect it's wrong https://github.com/openshwprojects/OpenBK7231...mits/277443b2a56f0343a84afe548b226ddbc5712a3f
#16 20995184 08 Mar 2024 07:56

p.kaczmarek2 p.kaczmarek2

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Post #16
20995184 08 Mar 2024 07:56

This may require one little change more. You need to add the related file to Make. Here is an example how I did that for power metering:
https://github.com/openshwprojects/OpenLN882H/commit/5e1e686bc5884ef0abee362bc791be660a541a2b

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
https://github.com/openshwprojects/OpenBK7231T
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#17 20999235 11 Mar 2024 08:35

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Post #17
20999235 11 Mar 2024 08:35

https://github.com/openshwprojects/OpenLN882H/pull/9
#18 21002110 13 Mar 2024 06:49

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Post #18
21002110 13 Mar 2024 06:49

is this good to try again? https://github.com/openshwprojects/OpenBK7231T_App/pull/1105
#19 21002234 13 Mar 2024 09:28

p.kaczmarek2 p.kaczmarek2

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Post #19
21002234 13 Mar 2024 09:28

If you have enabled this driver and updated the SDK, and it compiles fine with:
Code: text Expand Select all Copy to clipboard
#define ENABLE_DRIVER_BP5758 1

then you should next try using it on LN882H to see if driver is available.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
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#20 21002248 13 Mar 2024 09:35

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Post #20
21002248 13 Mar 2024 09:35

oh. I enabled the driver with #define ENABLE_DRIVER_BP5758 1

but does this need you to OK again it now before I can try a test workflow build?
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#21 21002253 13 Mar 2024 09:37

p.kaczmarek2 p.kaczmarek2

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Post #21
21002253 13 Mar 2024 09:37

I think that you can still click here:

and get the build files from the commit build.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
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#22 21002260 13 Mar 2024 10:11

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Post #22
21002260 13 Mar 2024 10:11

ah crap yes. you're right. AND I remember your guide says this 😳

Added after 30 [minutes]:

hmm

the latest bin does include driver enable in main https://github.com/openshwprojects/OpenBK7231...mits/277443b2a56f0343a84afe548b226ddbc5712a3f

and you've already merged the LN882H PR to add driver file for LNH882H https://github.com/openshwprojects/OpenLN882H/pull/9

so, not sure now
#23 21002388 13 Mar 2024 11:16

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Post #23
21002388 13 Mar 2024 11:16

Updating the SDK requires also a manual update of dependencies in the main App repository. I did it myself on the App, but did you merge my changes into your fork?

Still, if that were missing, then you'd get linker errors...

Oh, I've found a problem! We didn't have such define! We have just one large define for all 4 LED drivers:

Sorry, I should have caught it earlier.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
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#24 21002439 13 Mar 2024 11:52

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Post #24
21002439 13 Mar 2024 11:52

aha! that explains why I didn't see any other BP5758 defines for other chipsets

Does this mean all LED drivers under that umbrella define need adding to LN882H?
#25 21009462 18 Mar 2024 18:22

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Post #25
21009462 18 Mar 2024 18:22

is this correct?

https://github.com/openshwprojects/OpenLN882H/pull/10
#26 21009504 18 Mar 2024 18:49

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Post #26
21009504 18 Mar 2024 18:49

We can give it a try

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
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#27 21009643 19 Mar 2024 07:33

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Post #27
21009643 19 Mar 2024 07:33

failed on i2c drv. added. https://github.com/openshwprojects/OpenLN882H/pull/11

Added after 1 [hours] 11 [minutes]:

lol, sorry https://github.com/openshwprojects/OpenLN882H/pull/12

Added after 10 [hours] 17 [minutes]:

woohoo

Code: Text
Log in, to see the code

I just need to nail the BP5758D mappings
#28 21010121 19 Mar 2024 08:03

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Post #28
21010121 19 Mar 2024 08:03

Good job, but now, if we want to release it, you need to create a separate PR, because your PR also enables that unusual LED driver on Beken...

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
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#29 21010159 19 Mar 2024 09:17

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Post #29
21010159 19 Mar 2024 09:17

yes. I have been wondering about that. Does it have to be a new PR or can I remove that LED segment driver commit only and rename the PR? I'll investigate

Added after 29 [minutes]:

https://github.com/openshwprojects/OpenBK7231T_App/pull/1131
#30 21010227 19 Mar 2024 09:57

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Post #30
21010227 19 Mar 2024 09:57

Both approaches are acceptable. Let me check out the new PR.

I am creating multiplatform open source firmware (Tasmota replacement), right now supporting BK7231T, BK7231N, XR809, BL602, W800, W600, LN882H and soon supporting RTL and W701:
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Topic summary

✨ The discussion centers on disassembling and setting up a Tuya-based RGB smart light bulb featuring the LN882HKI chip and a BP5758D LED driver. Initial disassembly was straightforward, and the user successfully backed up the chip firmware and flashed OpenBK (OBK) firmware at 115200 baud after failed attempts at higher speeds. Challenges included identifying correct GPIO pins for PWM control and interfacing with the BP5758D chip, which requires proper SDA and SCL pin mapping. Continuity testing with a multimeter was advised but caused device damage when performed on a powered device. Contributors developed and shared device templates and firmware patches to enable BP5758D driver support on LN882H-based bulbs, including pin mappings and LED channel configurations (e.g., "BP5758D_Map 3 4 2 0 1" and "2 1 0 3 4"). Thermal management issues were noted, with CPU temperatures reaching up to 100°C at full brightness, prompting recommendations to limit brightness and use BP5758D_Current commands to reduce power. Stability concerns remain, especially with MQTT and RGB loops causing disconnections. Firmware dumping tools and flashing procedures were discussed, including correct wiring for UART pins (notably reversed TX/RX lines) and boot mode pin grounding (P21/A9). The community shared resources such as firmware repositories, device templates, and documentation links to assist with flashing, configuration, and troubleshooting. The final confirmed device model is W509Z2, a 220V 9W E27 ES RGB+CCT bulb with LN882H chip and BP5758D LED driver. The discussion also touched on thermal imaging equipment for temperature assessment and comparisons of power management between original and custom firmware.
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[LN882HKI] Tuya Smart Light disassembly and seek some help to set it up

FAQ

TL;DR: For OpenBeken users modding LN882H Tuya bulbs, the proven setup is 115200 baud, BP5758D on A0/A1 for the E14 bulb, and "LED_Map 3 4 2 0 1" or "BP5758D_Map 2 1 0 3 4" depending on model. This FAQ solves freezing GPIO scans, bad pin guesses, overheating, and backup issues before flashing. [#21010588]

Why it matters: These bulbs are cheap and moddable, but one wrong continuity test or current setting can destroy the lamp or make it unstable.

Variante	Chip	LED-Treiber	Bekannte Daten-/Taktpins	Bewährtes Mapping
Tuya W505Z2, 220V 9W E14 Candle RGB+CCT	LN882H	BP5758D	Pin 0 = CLK, Pin 1 = DAT	`LED_Map 3 4 2 0 1`
Tuya W509Z2, 220V 9W E27 RGB+CCT	LN882H	BP5758D	Pin 5 = DAT, Pin 6 = CLK	`BP5758D_Map 2 1 0 3 4`
Frühe Fehlannahme	LN882H	PWM vermutet	GPIO-Finder friert ab, LEDs reagieren nicht	Nicht per PWM einrichten

Key insight: The bulb is not a simple PWM LED design. Once the thread identified a BP5758D driver and the exact DAT/CLK lines, OpenBeken setup became a mapping-and-current problem, not a GPIO-finder problem. [#20970790]

Quick Facts

The original buyer paid 2.69€ for the bulb, which explains why several users treated it as a low-cost test platform for LN882H flashing and teardown work. [#20971840]
Confirmed stable flash speed was 115200 baud after 3 failed attempts at 2000000 baud on the same LN882H module. [#20970052]
Reported chip temperatures ranged from about 63°C idle/off to 100°C at full brightness, with several users reducing BP5758D current to improve stability. [#21011100]
The E14 candle template used Pin 0 = BP5758D_CLK;0 and Pin 1 = BP5758D_DAT;0, while the E27 template used Pin 5 = BP5758D_DAT;0 and Pin 6 = BP5758D_CLK;0. [#21280147]
On one stable E27 test, limiting current to 10 mA held chip temperature around 67.1°C after 2 hours at full brightness. [#21653825]

1. How do I set up an LN882HKI Tuya smart light in OpenBeken when the GPIO finder freezes and the LEDs do not respond?

Set it up as a BP5758D bulb, not as a PWM bulb. The freeze on pins like P13/P14 misled early testing, but the thread later confirmed this hardware uses a BP5758D LED driver over two control lines. Start by tracing DAT and CLK with a multimeter, assign those pins in OpenBeken, then apply the correct map command for your model. For the E14 candle bulb, the working result was LED_Map 3 4 2 0 1 after BP5758D support was enabled. [#21010588]

2. What is the correct OpenBeken template for the Tuya W505Z2 220V 9W E14 candle RGB+CCT bulb with LN882H and BP5758D?

The working template uses model W505Z2, chip LN882H, and BP5758D on pins 0 and 1. Set pin 0 to BP5758D_CLK;0 and pin 1 to BP5758D_DAT;0. The posted template also identifies it as a 220V 9W E14 Candle RGBCCT Bulb (2800K-6500K) with flags 1024. After flashing, users still needed the color-channel mapping command to match the LED order correctly. [#20994908]

3. Which LN882H pins are connected to the BP5758D on this bulb, and how do I identify SDA and SCL with a multimeter?

On the first E14 bulb, A0 was connected to SCL and A1 to SDA. The PCB had both SDA and SCL marked, so the safe method was to check continuity from those PCB labels to the LN882H module pads with power removed. 1. Unplug mains power completely. 2. Put the meter in continuity or beep mode. 3. Probe from BP5758D SDA/SCL pads to LN882H pins until you find the matches. That process produced the final A0/A1 identification. [#20971840]

4. What is the safe way to do a continuity test on a smart bulb PCB, and why can testing on a powered device burn components?

Do continuity tests only with the bulb fully disconnected from mains. One user tested while the lamp was powered, saw a small electrical flash, and then found burn marks and a dead bulb. Another poster explicitly clarified that continuity mode is the meter's beep mode and that the bulb does not need power for that test. A live continuity test can inject current into the wrong part of the circuit and damage components instantly. [#20971601]

5. Why does flashing OpenBeken to an LN882H bulb work at 115200 baud but fail repeatedly at 2000000 baud?

Because this LN882H setup proved reliable at 115200 and unreliable at 2000000 on real hardware. The original poster reported three failed flash attempts at 2000000 baud, then an immediate success at 115200. The thread did not identify a deeper firmware bug, but it clearly showed that lower speed was the practical fix for this bulb and wiring setup. Use 115200 first if you want a dependable backup or flash session. [#20970052]

6. How do I use BP5758D_Map and LED_Map in OpenBeken to get the correct RGB+CCT channel order on these Tuya bulbs?

Use the mapping command that matches your bulb model and driver pins. For the E14 W505Z2 candle bulb, the working channel order was LED_Map 3 4 2 0 1. For the E27 W509Z2 bulb, the final working order was BP5758D_Map 2 1 0 3 4. "BP5758D is a 5-channel constant-current LED driver that controls RGB+CCT LEDs over DAT/CLK lines, unlike simple PWM wiring where each LED channel connects directly to a microcontroller pin." That difference is why mapping fixes colors here. [#21281700]

7. What BP5758D current settings keep LN882H bulbs stable and cooler without losing too much brightness?

The thread's safest proven range was low current, especially 1 1, 2 2, or 3 3. One user reported BP5758D_Current 3 3 gave full-brightness operation with about the same temperature as before, around 63°C off afterward. Another reported BP5758D_Current 2 2 held about 80°C with no reboot or freeze after 2 hours. Later testing showed BP5758D_Current 1 1 could keep a similar bulb stable around 73°C. [#21650565]

8. Why do LN882H smart bulbs with BP5758D run hotter under OpenBeken than under the factory Tuya firmware?

The thread points to LED current, not a confirmed OpenBeken power-save bug, as the main reason. Users saw temperatures climb to 100°C at full brightness under OpenBeken, then improve when they lowered BP5758D current. One contributor concluded that OBK's default BP5758 current was likely higher than the factory setting used by these bulbs. Another noted LN882H itself runs hot, so the bulb combines a warm SoC with a high-current LED driver in a cramped enclosure. [#21650616]

9. What is BP5758D, and how does it differ from PWM-controlled LED setups in Tuya smart bulbs?

BP5758D is a dedicated LED driver chip, not a direct PWM output scheme. It controls five LED outputs for RGB+CCT bulbs through two digital lines named DAT and CLK, which the thread also called SDA and SCL. PWM-controlled bulbs instead use LN882H pins that drive LED channels directly, so only certain PWM-capable pins matter there. This bulb confused early setup because users first looked for PWM GPIOs, but the hardware actually centered on a BP5758D on the LED board. [#20970624]

10. What is GPIOA9 on the LN882H, and why is it used as the BOOT pin for entering download or flash mode?

GPIOA9 is the LN882H BOOT pin used to force download mode for flashing or dumping firmware. The thread later clarified that BOOT/GPIOA9 is pin 17 on LN882HKx modules, and one user verified that their board label P21 was actually continuity-linked to A9. Pulling that BOOT line low during startup was the key step for entering flash mode when backup tools reported that the chip could not enter download mode. [#21266733]

11. How do I dump and back up LN882H firmware before flashing OpenBeken, especially when the LN882H_Flash_Dumper tool gives Python or file errors?

Use the dumper only after you verify Python version, tool files, UART pins, and BOOT wiring. One Linux user got a SyntaxError on print('.', end='', flush=True), which points to running the script with an older Python version. On Windows, another common failure was a missing LN882H_CMD_Tool.exe in the same directory as the dumper script. If backup still fails, confirm BOOT on GPIOA9, use the correct UART, and retry before flashing any OpenBeken release. [#21265486]

12. LN882H Flash Dumper on Windows vs Linux: what are the common setup mistakes and how do I fix serial port, missing file, and download-mode problems?

The common mistakes were old Python on Linux, a missing EXE on Windows, wrong UART pins, and wrong BOOT pin handling. 1. On Linux, run the dumper with a Python version that supports print(..., end=..., flush=...). 2. On Windows, keep LN882H_CMD_Tool.exe in the same folder as LN882H_Flash_Dumper.py. 3. If you get "could not go in download mode," short GPIOA9/BOOT to ground during reset and verify you are using the flashing UART, not just the boot-log UART. [#21266966]

13. What's the best way to remove and disassemble these cheap Tuya LED bulbs without damaging the fragile threaded center or internal parts?

Open the bulb gently and avoid forcing the fragile threaded center from the front. A later user bent that center coil or threaded part, then realized it could likely be pushed out through the two holes inside instead of being re-threaded by force. Earlier in the thread, the original poster said disassembly was easy after following an Elektroda channel video and did not damage the lamp. That combination suggests careful mechanical pressure and inside-out removal is safer than twisting fragile parts. [#21554929]

14. How can I tell whether my Tuya RGB+CCT bulb model is W505Z2 or W509Z2 from the factory firmware, Tuya app, or boot log?

The cleanest method is to pair the factory firmware in the Tuya app and read the model shown there. The E14 candle template was published as W505Z2, while another LN882H RGB+CCT bulb was later confirmed as W509Z2 after reflashing factory firmware and pairing it again. A boot log alone showed product keys and firmware versions, but the model confirmation in the thread came from app pairing, not from a decoded boot string. [#21712747]

15. What UART pin wiring should I use for LN882H backup and flashing when boot logs appear on U1 but flashing needs U0 or reversed TX/RX lines?

Use the UART that the tool expects for flashing, and cross TX/RX even if your boot log came from another port. One later user with a similar board reported successful flashing and backup only after using reversed lines: U0-TX -> RX, U0-RX -> TX, GND -> GND, 3V3 -> 3V3, and P21 -> GND during boot. That same post warned that boot logs can appear elsewhere, so a readable log on U1 does not prove U1 is the right flashing port. [#21554929]

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