STM32l432KB Based Custom Board

[NItin Kanani]

Posted on February 27, 2018 at 13:12

Hi All

i will use STM32l432KBU6 5x5 package

So please suggest me how much value external crystal use for main clock.

Regards

Nitin 

#stm32l432 #stm32-l4

[Andrew Neil]

Posted on February 27, 2018 at 13:55

Surely that's up to you to choose - in accordance with your project requirements?

[NItin Kanani]

Posted on February 27, 2018 at 13:57

if i use 32.678khz is it ok?

[Andrew Neil]

Posted on February 27, 2018 at 14:01

If it meets 

your project requirements, then yes.

[NItin Kanani]

Posted on February 27, 2018 at 14:15

i put 

32.678khz in my custom hardware

scenario is my hardware is connect to st link v2 debugger

i generate code trough Cubemax and open in keil 5

Debugger is  is deted in keil

But Code is not running.  

.

[Tesla DeLorean]

Posted on February 27, 2018 at 14:38

I probably would have chosen 32.768 KHz it is more of a standard value, of course one would also need to pay attention to whether it was a 6, 9 or 12pF version too, and picked the right capacitors.

The L4 should run just fine of the internal MSI at 4 MHz, you should perhaps try doing that first.

Also the ST-LINK firmware looks to be super old, consider updating that.

Do you have a schematic and component values for this custom board? It might be easier than this guess what's not working game.

[NItin Kanani]

Posted on February 27, 2018 at 14:46

Hi Dear 

Thanks for Reply me 

please find schismatic of controller broad

give me answer ASAP

[Tesla DeLorean]

Posted on February 27, 2018 at 15:05

ASAP only works if you're paying the freight costs.

The 12pF C8/C9 seems awfully high, do you have the specs for the crystal you chose and the computations from the STM32 Crystal App note to support that choice?

The STM32's generally do a lot better with 32.768 KHz 6-7pF crystals, and a pair of 2.7pF caps, but that's usually off the OSC32 pins.

I would also pull BOOT0/PH3 low, with perhaps a 10K or 47K

Again make a project using the MSI clock the part starts with and get that working, then move to the crystal reviewing the code that starts it, making sure it starts, and exporting it via the MCO pin so you can confirm it is oscillating properly.

[NItin Kanani]

Posted on February 28, 2018 at 06:50

is there any document which describe for

'

pull BOOT0/PH3 low'.

please share the document.

your suggested option is not mention in datasheet.can u please share.