cancel
Showing results for 
Search instead for 
Did you mean: 

JTAG remapping pin PB4

longTimer
Associate II
Posted on October 04, 2011 at 02:20

Hi,

I am using an STM32F102C6 processor.  The design has an LED and resistor tied to 3.3V and Pin PB4.  I need to release this pin from JTAG and use it in OD mode to drive the LED.

So far I have:

Read all the documentation on pin remapping and selected the third JTAG option that remaps PB3 and PB4.

Checked all the other re-mappings for this part and concluded that they do not affect PB4 unless enabled.

Tried configuring the pin in both Out_OD and Af_OD modes with no results.

Tried everything on multiple boards.

Am I missing something?  It doesn't seem like this should be so difficult.

Thanks for your ideas.

Dave

#jtag-pb4-remap #answer
1 REPLY 1
longTimer
Associate II
Posted on October 04, 2011 at 21:05

Solution:

It was not obvious from the chip documentation that the AFIO feature is a clocked preipheral.  Its clock needs to be enabled as follows:

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

Also, you do not need to use the 'af_OD' pin option even though the table in the documentation makes it look that way.  Use 'Out_OD' or the other 'Out_' option of your choice. 

Thanks to Alec at ST.

Dave