FAQ
TL;DR: To flash a MOES MS-104B (WB2S), wire RX, TX, GND, and 3.3V; "make sure to power WiFi module from 3.3V". Select BK7231T in the OpenBK tool. [Elektroda, p.kaczmarek2, post #21577980]
Why it matters: This FAQ helps DIY tinkerers safely wire FT232RL to WB2S and complete OpenBK7231T flashing without 3.3V damage or miswiring.
Quick Facts
- WB2S UART pads are on the bottom side of the module on this board. [Elektroda, p.kaczmarek2, post #21577937]
- Set the FT232RL to 3.3V; weak board LDO current can cause flash failures; choose BK7231T in the tool. [Elektroda, p.kaczmarek2, post #21577980]
- Flashing typically needs a quick 3.3V power-cycle; don’t solder to converter pins so you can toggle power. [Elektroda, p.kaczmarek2, post #21580195]
- USB-only 3.3V from an FT232RL worked once here (1 confirmed success). [Elektroda, dominikgaspar123, post #21580243]
- After flashing, add PowerSave 1 to Startup to reduce consumption. [Elektroda, p.kaczmarek2, post #21580248]
Which pins do I connect between WB2S and an FT232RL to flash OpenBK7231T?
Use four lines: RX, TX, GND, and 3.3V. Keep wiring short and avoid swapping lines. The guidance was to use RX, TX, GND, and 3.3V, following the demonstrated approach. Set your converter for 3.3V operation. [Elektroda, p.kaczmarek2, post #21578303]
Where are the RX/TX pads on the MOES MS-104Bs WB2S?
On this board, the WB2S RX and TX pads are on the bottom of the module. They are not visible from the top side. Access the underside pads for UART wiring. [Elektroda, p.kaczmarek2, post #21577937]
I soldered to CEN, AD, PWM0, PWM1why doesnt flashing work?
Those are not UART pads, so the bootloader wont see your adapter. They are control and PWM-related pins. "Youve soldered to: CEN, AD, PWM0, PWM1." Move your wires to the RX/TX pads on the bottom. [Elektroda, p.kaczmarek2, post #21578633]
Should I desolder the WB2S module to flash it?
Yes if you want the most reliable path. Desolder the daughterboard with WB2S and flash it directly. In-circuit flashing may still work if RX/TX arent tied to other logic. It depends on how the main board uses those lines. [Elektroda, p.kaczmarek2, post #21577832]
Can I flash using only the FT232RLs 3.3V from USB?
Yes. In this thread, one user confirmed success using only the FT232RLs USB-powered 3.3V. After flashing, their switch worked normally. This is one confirmed case of USB-only power working. [Elektroda, dominikgaspar123, post #21580243]
Do I need to power-cycle 3.3V during flashing?
Yes. The flashing process needs a quick disconnect and reconnect of the 3.3V rail. Soldered power wires make this harder to do cleanly. Use a switch or jumper so you can toggle 3.3V on cue. [Elektroda, p.kaczmarek2, post #21580195]
Is it okay to solder directly to FT232RL pins?
Avoid that. "You should not solder to USB to UART converter pins..." It complicates quick power-cycling and can stress the adapter. Use removable connections instead of hard-soldering to the adapter. [Elektroda, p.kaczmarek2, post #21580195]
Which chip target must I select in the OpenBK tool for WB2S?
Select BK7231T in the flashing tool. The WB2S module uses a BK7231T-class chipset, so choose the BK7231T target. This matches the maintainers guidance for WB2S. [Elektroda, p.kaczmarek2, post #21577980]
What flashing tool should I use?
Use the OpenBK7231 GUI Flash Tool from OpenSHWProjects. Its the recommended utility referenced by the project maintainer in this thread. Install it before wiring and flashing the module. [Elektroda, p.kaczmarek2, post #21577937]
Why does my flash fail at 0% or disconnect mid-way?
Power delivery is a common cause. "If there is no good LDO that can provide enough current on your board, then flashing may fail." Power the module with a stable 3.3V source and minimize voltage drop. [Elektroda, p.kaczmarek2, post #21577980]
How do I do the quick 3.3V power-cycle when flashing?
Use this 3-step approach:
- Disconnect 3.3V to WB2S.
- Start the flash so the tool waits for boot.
- Reconnect 3.3V quickly to enter flashing mode.
This is easier if power isnt hard-soldered. [Elektroda, p.kaczmarek2, post #21580195]
Any post-flash configuration tips for OpenBK on WB2S?
Enable power saving. Add the command PowerSave 1 to your Startup commands after flashing. The maintainer specifically recommended enabling this setting for your device. [Elektroda, p.kaczmarek2, post #21580248]
