STM32F103 read analog signal

[lemac]

Posted on April 14, 2015 at 09:55

Hello

I have a nucleo STM32F103, I put a  external clock of 25MHz.How can i read a analog signal conected in PB8?Someone can help me??Best regards #analog-input #nucleo-f103rb

[l239955_stm1]

Posted on April 14, 2015 at 14:21

- set ADC configuration, enable adc channels, GPIO set as ''analog mode''

- set DMA channel  configuration - transfer analog value to memory through DMA

[raptorhal2]

Posted on April 14, 2015 at 15:20

ADC analog channels have fixed pin assignments, unlike other peripherals which may have a choice of pins. PB8 is not an ADC channel.

Read the data sheet Section 3 Pin Assignments table and choose an appropriate pin e.g., PA1. Whichever peripheral library you are using will have ADC examples you can adapt for your project. Cheers, Hal

[lemac]

Posted on April 16, 2015 at 18:40HelloI changed this signal from PB8 to PB1 and my code continue without work.I am using the sample code stsw-stm32028but i don't understand veyr well it.Someone can send me code example?Best Regards

[Tesla DeLorean]

Posted on April 16, 2015 at 19:50

Download the STM32F1 firmware library, there are ADC examples in that.

http://www.st.com/web/en/catalog/tools/PF257890

Ignore the Cube messaging, go to the red download button at the bottom.Not sure it's going to be useful for a 25 MHz signal, but that's either poorly expressed, or unrelated.You have an F103 or F105 part?

[raptorhal2]

Posted on April 16, 2015 at 19:54

The STM32028 examples should work on your nucleo with simple adaptation.

PB1 is ADC123 channel 9. None of the 7 examples in STM32028 use Channel 9. Which of the 7 examples are you using? Did you change the example channel to channel 9? Unless we see the code, we can only guess what is wrong. Regards, Hal

[lemac]

Posted on April 17, 2015 at 08:23

Hello

All right Clive1: I have a Nucleo-F103RB but i changed the microcontroller and i put a STM32F I put a external clock at 25MHz. It is very similar to my final product Baird.hal.001: I am using the example with this path ''stsw-stm32028\STM32F10x_AN3116_FW_V1.0.0\Project\ADC Modes\SingleChannelContinuous'' I changed GPIO_Configuration

GPIO_InitTypeDef GPIO_InitStructure;

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOB, &GPIO_InitStructure);

And now I chaged ADC_Channel_14 for ADC_Channel_9 Now all work. I only have a final question. can i use Port PB8 for analog adquisition??? Best regards

[Tesla DeLorean]

Posted on April 17, 2015 at 12:33

I only have a final question. Can i use Port PB8 for analog acquisition???

The

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00220364.pdf

says it's not connected to an ADC, so no. Didn't Hal already mention that?