ChibiOS Free Embedded RTOS

I have an application on an stm32l432 which uses both i2c and adc. i2c works fine except if I execute

adcStart(&ADCD1, NULL)

the adc works fine once I start it, but if the adc is started, the i2c i2cMasterTransmitTimeout(..) command returns an error code -- even if the only adc command executed is the adcStart command. Something in the initialization code is stepping on the i2c, but I haven't got a clue where to look.



Kernel: 4.0.0
Compiler: GCC 5.4.1 20160609 (release) [ARM/embedded-5-branch revision 237715]
Architecture: ARMv7E-M
Core Variant: Cortex-M4
Port Info: Advanced kernel mode
Platform: STM32L4xx Ultra Low Power
Board: STMicroelectronics STM32 Nucleo32-L432KC
Build time: May 30 2017 - 18:45:04

Hi,

Is there a DMA conflict? check the channel assigned in mcuconf.h.

Moved in STM32 support.

Giovanni

There doesn't seem to be a channel conflict -- ADC1 is on channel 1, I2C1 on channels 6 & 7.

Geoffrey

I have no clue of what could cause this...

Is it just adcStart() or also some pin mode change or other things?

Giovanni

Just executing adcStart is sufficient to break I2C.
Geoffrey

Is adcStart() placed before i2cStart() or after? does it make a difference? are debug options enabled in chconf.h?

Giovanni

Students of mine have made a project, (an autonomous stoplight for bicycle) using stm32l432, they use I²C for IMU access, and ADC for testing battery level, and they did not mention me any incompatibility problem between I²C and ADC on stm32l432.

Alexandre

I look elsewhere in my code for the problem.
Geoffrey

You could also share us the main...