[SOLVED] Nucleo STM32l4R5ZI Vref Buffer stuck on Timeout

[DMart.16]

Hello,

I am trying to output the reference voltage for the DAC in a Nucleo L4R5ZI, I am doing so with the Vref Buffer. I am using STM32CubeIDE.

After creating a default project I just disabled all the communication I wasn't going to need and I configured the Vref Buffer in the SYS tab: Scale 0 (2.048v) and as output.

CubeMX generates a project that doesn't work. After some debuging I found that the function: HAL_SYSCFG_EnableVREFBUF() returns a timeout. After a search in Google I found a similar question and the solution given was to enable the RCC SYSCFG clock before hand, but that is enabled a couple of lines before enabling the Vref Buffer in my generated code, so that appears to not be the problem.

I am not sure if the problem is in the actual timeout (some problem with the clock) or if the Vref Buffer is just not being enabled propperly, thus causing the timeout.

I can't get it to work, I have uploaded the .ioc file in case you want to try it out.

Thank you so much

[waclawek.jan]

How is the VREF+ pin connected externally?

Get the schematics to your board and check the related solder bridges.

JW

[TDK · Accepted solution]

You'll need to disconnect VREF+ from AVDD by removing SB149.

 

[DMart.16]

That was it!

I also had to bridge (was OFF, now ON) SB119 to access VREF+ via Pin 6 of CN7 and Pin 7 of CN12.

Thank you so much!