Issue with SPI between BMSCCTX and C4MINI

Zen432 · ‎2025-12-12

Hello team,

I am using the GUI demo (single) for BMSCCTX and C4MINI with 4 LFP Batteries. I have followed the steps described by @ritehracingteam in this thread.

After I run the program from the AutoDevKit Studio, my D9 and D2 LED are lit up and D8(Blue) is blinking. D7 remains turned off. Which according to the documentation means SPI is not working.

I made sure Hotplug connection is made and the pin configuration is correct, also checked all the connections.

Is there something I might be missing?

Regards,

Zen

SRomeo · ‎2025-12-15

Hi there,
Yes, it seems your SPI communication was not established.

This usually means C4MINI SPI line is not connected correctly, or the SPI signals are not generated.
First of all, check C4MINI Jumpers and retry:

If this doesn't solve your issue, I suggest you check once again C4MINI pin connection.

If you are using "AEK-MCU-C4MINI - AEK_POW_BMSCCTX_GUI_application for discovery" AutoDevKit demo project, make sure your connection are the following.

Please, consider that this demo project has to be used as it is.

Any modification to the BMS configuration via BMS component, (and further allocation) will surely change your board connections.

Best regards,
Simone
AEK_Team

Zen432 · ‎2025-12-18

Hey Simone,

Thanks for the reply.I checked the connections and the Jumpers they are in the correct configuration as you suggested.

I am attaching the Oscilloscope reading please see them. The SCK reading is similar to @ritehracingteam issue, but the hotplug connection is there. I measured the voltages and found:

VREG = 6.6V, VCOM = 5V, VANA = 3.3V but VTREF = 0. I believe this is the default setting for the L9963E from datasheet. Although in the BMSCHAIN component VTREF is set to always on (5V). ISOLp and ISOLm are both +1.2V w.r.t to GND_BMS. I don't see any activity.

I also tried connecting the hotplug connection to VREG instead of VTREF, same results no changes.

Regards,

Zen

Zen432 · ‎2025-12-28

Hey Simone,

I tried changed the SCK pin setting from weak drive to strong drive since the clock was not square(See pic), still no D7 LED. Moreover after changing any setting in the demo the D2 LED doesn't light up. It only works with the demo as is. Is the L9963T faulty? Should I get a new board?

Regards,

Zen

Weak DriveStrong Drive