BBAI Cloud9 BlinkExternalLED pru example LED does not blink

[pierric...@gadz.org]

Hi all, 

I am trying to run the PRU example under /var/lib/cloud9/BeagleBone/AI/pru/blinkExternalLED.pru1_1.c and it is not working. 

It compiles with the Makefile and after placing the firmware under pru1_1 core (cp blinkExternalLED.pru1_1.out /lib/firmware/am57xx-pru1_1-fw), the pru start correctly (according to dmesg -Hw) with (echo 'start' > /sys/class/remoteproc/remoteproc5/state).

 However, I do not see any LED blink on P9_25 of my beaglebone AI. 

I have checked: 

• the  GPIO6_17 DATAOUT register is changing  every 0.5s  according  to devmem2 (sudo devmem2 0x4805D13C) but the LED is still not blinking. 
  
• pinmuxing is such that /opt/scripts/device/bone/show-pins.pl gives "P9.25                    165  D18 e fast    down gpio6_17" so it's seem to be configured correctly.

Can anyone help me? 

Best

Pierrick