>>21763803 Hi josemr,
I've been working non-stop on this exact issue for the past 48 hours, and unfortunately I have to share some frustrating findings.
What I tested:
I successfully compiled a custom firmware with ENABLE_BL_TWIN explicitly enabled in the obk_config.h file, along with both ENABLE_DRIVER_BL0942 and ENABLE_DRIVER_BL0942SPI. The firmware compiled and flashed without errors.
Results:
With standard BL0942 driver: Same as you - only ONE clamp reading appears (voltage/frequency work, but zero current/power)
With BL0942SPI driver: The device becomes unstable and won't boot properly if started automatically
Logs show constant checksum errors: Failed to read reg 03/04/06/07/08: bad checksum 00 wanted A4/A3/A1/A0/9F
Root cause analysis:
After extensive testing with both mains power connected and loads on the clamps, the conclusion is clear: The firmware CANNOT handle two BL0942 chips on a shared UART (which is exactly how the QS-wifi-S10-CT02 is wired - both U1 and U2 TX/RX are paralleled to the same CB2S UART pins).
The checksum errors prove that:
Both BL0942 chips ARE responding
Their data frames collide/overlap when transmitted simultaneously
The OpenBK7231N driver has no protocol to address/multiplex between the two chips
Even with ENABLE_BL_TWIN active, the code lacks the logic to handle this specific hardware architecture
Hardware confirmation:
I physically traced the PCB - both BL0942s share the same UART bus (not UART1/UART2 separately like other dual-meter designs). This is fundamentally incompatible with the current driver implementation.
Bottom line:
Even with a properly compiled ENABLE_BL_TWIN firmware, this hardware will not work as dual-channel without significant driver code modifications to implement collision avoidance or sequential polling.
The ENABLE_BL_TWIN flag exists in the codebase but appears to be designed for different hardware architectures (separate UARTs), not for shared-UART configurations like ours.
Recommendation:
We need either:
A driver patch specifically for "twin BL0942 on shared UART"
Or use the device with only one clamp until proper support is added
I'm planning to open a GitHub issue on the OpenBK7231T_App repository with full logs, PCB photos, and technical details to request native support for this hardware.
Anyone else hitting this wall?
----
Skasowano z tematu: QS-wifi-S10-CT02 (CB2S) Flashing Guide for Offline Firmware Installation
przez toufou54 dnia 27 Nov 2025 18:27
I've been working non-stop on this exact issue for the past 48 hours, and unfortunately I have to share some frustrating findings.
What I tested:
I successfully compiled a custom firmware with ENABLE_BL_TWIN explicitly enabled in the obk_config.h file, along with both ENABLE_DRIVER_BL0942 and ENABLE_DRIVER_BL0942SPI. The firmware compiled and flashed without errors.
Results:
With standard BL0942 driver: Same as you - only ONE clamp reading appears (voltage/frequency work, but zero current/power)
With BL0942SPI driver: The device becomes unstable and won't boot properly if started automatically
Logs show constant checksum errors: Failed to read reg 03/04/06/07/08: bad checksum 00 wanted A4/A3/A1/A0/9F
Root cause analysis:
After extensive testing with both mains power connected and loads on the clamps, the conclusion is clear: The firmware CANNOT handle two BL0942 chips on a shared UART (which is exactly how the QS-wifi-S10-CT02 is wired - both U1 and U2 TX/RX are paralleled to the same CB2S UART pins).
The checksum errors prove that:
Both BL0942 chips ARE responding
Their data frames collide/overlap when transmitted simultaneously
The OpenBK7231N driver has no protocol to address/multiplex between the two chips
Even with ENABLE_BL_TWIN active, the code lacks the logic to handle this specific hardware architecture
Hardware confirmation:
I physically traced the PCB - both BL0942s share the same UART bus (not UART1/UART2 separately like other dual-meter designs). This is fundamentally incompatible with the current driver implementation.
Bottom line:
Even with a properly compiled ENABLE_BL_TWIN firmware, this hardware will not work as dual-channel without significant driver code modifications to implement collision avoidance or sequential polling.
The ENABLE_BL_TWIN flag exists in the codebase but appears to be designed for different hardware architectures (separate UARTs), not for shared-UART configurations like ours.
Recommendation:
We need either:
A driver patch specifically for "twin BL0942 on shared UART"
Or use the device with only one clamp until proper support is added
I'm planning to open a GitHub issue on the OpenBK7231T_App repository with full logs, PCB photos, and technical details to request native support for this hardware.
Anyone else hitting this wall?
----
Skasowano z tematu: QS-wifi-S10-CT02 (CB2S) Flashing Guide for Offline Firmware Installation
przez toufou54 dnia 27 Nov 2025 18:27
