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2014

Nice bit of information at this TI URL:

(My underlining below):

 

PRU Development

The Programmable Real-time Unit (PRU) is a low-latency microcontroller sub-system comprised of two or more 32-bit RISC processors, local instruction and data RAM, local peripherals and an interrupt controller. The PRU is efficient at handing events that have tight real-time constraints. The PRU is also known as the Industrial Communications Sub-System since it is used to enable industrial protocols such as EtherCAT®, EtherNet/IP™, PROFINET, PROFIBUS, POWERLINK, SERCOS III, and others. Each 32-bit processor runs at 200MHz, enabling 5ns instruction cycle. Local peripherals within the PRU sub-system include UART, eCAP, MII_RT, MDIO and IEP. The PRU’s fast input and output pins enable detection and reaction to I/O events within two PRU cycles.

Code Composer Studio provides a C compiler enabling users to add differentiation to their products.

 

(Downloading now! )

 

bbb-pru-c.png

I've previously had great results connecting Adafruit 8x8 LED matrix displays to the BeagleBone Black via I2C:

 

I decided to try out the Adafruit bi-color 8x8 LED matrix and hooked it up with the same I2C pins as before.  You'll need to setup the Adafruit_BBIO Python library if you haven't already:

https://learn.adafruit.com/setting-up-io-python-library-on-beaglebone-black/overview

 

You'll also want to grab the Adafruit Python libraries for the Raspberry Pi since they work on BeagleBone Black, too:

https://github.com/adafruit/Adafruit-Raspberry-Pi-Python-Code

 

Here is the BegaleBone Black running the demo program ex_8x8_color_pixels.py from the repo:

https://github.com/adafruit/Adafruit-Raspberry-Pi-Python-Code

 

BeagleBone Black & Adafruit 8x8 bi-color matrix

https://www.youtube.com/watch?v=vnHC6bVj5bc

 

I thought it would be interesting to plot the readings from a sensor over time on the matrix with different colors representing the magnitude of the reading:

20140116_104027.jpg

 

I hooked up a pot to the analog input to simulate a sensor.  Here's the Python script:

https://github.com/pdp7/beaglebackpack/blob/master/plot.py

 

It is Invoked by this shell script so that PYTHONPATH will be set:

https://github.com/pdp7/beaglebackpack/blob/master/plot.sh

 

BeagleBone Black: plot analog sensor on Adafruit bi-color LED matrix

https://www.youtube.com/watch?v=QQNqxHQDj5E

 

Cheers,

Drew

http://twitter.com/pdp7