STM32F4 Discovery SPI problem

flukeco · ‎2014-07-07

Posted on July 07, 2014 at 12:48

Hi,

I've successfully implement SPI communication between STM32F4 Discovery (as master) and PIC18F2580 (as slave). Everything works fine, clock signal is sent from STM32F4, MOSI and MISO data are correct.

However, when I tried the opposite configuration (PIC18F2580 as master and STM32F4 as slave), no clock signal is sent from PIC's SCK pin (SCK always at high, I confirmed this using logic analyzer).

What do you guys think could be the source of this problem?

Does the CPU speed has effect on this (PIC has slower CPU speed than STM32F4 board)?

Any suggestions will be highly appreciated.

Best Regards,

Pat

francescatodiego · ‎2014-07-07

Posted on July 07, 2014 at 14:08

The first thing

that comes to my

mind

(and

you probably

already

tried)

is

disconnect

the

clock

and

see

if that

signal is present

on the master (PIC)

The

clock

of the two

different

cpu

has nothing to do

The

synchronous serial

uses

its own clock

to synchronize the

communication.