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by rfincher1
Wed Mar 13, 2013 6:00 pm
Forum: Automation, sensing and robotics
Topic: Generate 2 pwm signals
Replies: 33
Views: 10900

Re: Generate 2 pwm signals

We have been using the Adafruit PWM 16 board that gives you 16 PWM outputs with the 2 wire I2C connection. That gives us plenty of pwms to control two motors and numerous servos to control a robot arm. Here a tutorial on using it with the Pi: http://learn.adafruit.com/adafruit-16-channel-servo-drive...
by rfincher1
Mon Oct 08, 2012 5:13 am
Forum: Other projects
Topic: I2C bus - anyone planning to use it?
Replies: 30
Views: 18575

Re: I2C bus - anyone planning to use it?

It works with the Raspian Wheezy kernel driver, tested with Adafruit 16 channel pwm/servo driver (based on PCA9685). Java files: http://simonp.uw.hu/linuxi2c/linuxi2c_java_v0_1.zip Setup the i2c driver: http://www.skpang.co.uk/blog/archives/575 Install the proper jna package on raspberry and use th...
by rfincher1
Mon Sep 10, 2012 9:19 pm
Forum: Automation, sensing and robotics
Topic: I2C 16 Channel PWM/Servo Breakout - Working
Replies: 15
Views: 39625

Re: I2C 16 Channel PWM/Servo Breakout - Working

There is now a tutorial from Adafruit on connecting their 16 channel pwm board to the Pi:

http://learn.adafruit.com/adafruit-16-c ... pberry-pi/

It has a Python library.

Rick
by rfincher1
Wed Aug 22, 2012 5:49 pm
Forum: Raspbian
Topic: Java on Raspbian
Replies: 105
Views: 49470

Re: Java on Raspbian

This is from Henrik Stahl at Oracle: " One caveat is that the current binary is softfloat ABI only, so it won't work with (for example) the Raspbian distribution which uses the hardfloat ABI. We are planning to add hardfloat support in an upcoming JDK release, as well as support for JavaFX on ARM." ...
by rfincher1
Tue Aug 07, 2012 2:29 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: PWM and I2C aren't working together in Python
Replies: 7
Views: 1595

Re: PWM and I2C aren't working together in Python

Also a PCA9685 uses the I2C bus to give you 16 PWM outputs if you want to stick with I2C.

Rick
by rfincher1
Tue Aug 07, 2012 2:14 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: PWM and I2C aren't working together in Python
Replies: 7
Views: 1595

Re: PWM and I2C aren't working together in Python

You can use this chip via the SPI bus to control PWM: https://www.sparkfun.com/products/10136? This chip gives you 16 PWM outputs for a pretty low cost. You may also want to be sure you have a 5V power supply with at least 1 Amp powering the PI. If the power supply is near the edge you may be gettin...
by rfincher1
Mon Jul 23, 2012 4:54 am
Forum: Other programming languages
Topic: Java experiences?
Replies: 29
Views: 17760

Re: Java experiences?

Hi Chris, How did you get the Oracle embedded headless JVM installed? I installed the files on the Pi in /usr/share and setup JAVA_HOME and added the path to /usr/binbin. When I sudo java -version I get: java: error while loading shared libraries: libjli.so: cannot open shared object file: No such ...
by rfincher1
Mon Jul 23, 2012 4:29 am
Forum: Other programming languages
Topic: Java experiences?
Replies: 29
Views: 17760

Re: Java experiences?

[quote="chrisg"]I tested with three JVMs, using Java 6 for OpenJDK and Java 7 from Oracle. The reason for using the older OpenJDK is that I believe Cacao JIT isn't (or wasn't) yet supported on OpenJDK 7 in the standard Debian packages. Hi Chris, How did you get the Oracle embedded headless JVM insta...
by rfincher1
Thu Jun 28, 2012 4:50 am
Forum: Other projects
Topic: Adding a small touch screen to the pi
Replies: 11
Views: 9859

Re: Adding a small touch screen to the pi

See: http://elinux.org/RPi_Screens for discussion about screens Also this: http://www.raspberrypi.org/phpBB3/viewtopic.php?f=7&t=5493 DSI drivers aren't written to work with the graphics chip yet, but if you just want to show pictures you could write a program to do that. Not a trivial program, thou...
by rfincher1
Wed Jun 27, 2012 6:43 pm
Forum: Other projects
Topic: Touchscreens for Raspberry Pi
Replies: 105
Views: 176863

Re: Touchscreens for Raspberry Pi

Don't know what your price point is but the one in the link below may work for you. You'll need a calibrating program for the touch screen, but several are available for Debian. http://www.aliexpress.com/product-fm/581324540-DHL-free-shipping-10-touch-screen-LCD-Monitor-with-1600-1200-1080P-HDMI-who...
by rfincher1
Wed Jun 27, 2012 6:41 pm
Forum: Other projects
Topic: 8.9 touch screen solution
Replies: 17
Views: 13916

Re: 8.9 touch screen solution

Here's a touch screen monitor with 1600x1200 and 1080p that runs on 12 volts for $148 USD, free shipping. USB interface for the touch screen:

http://www.aliexpress.com/product-fm/58 ... alers.html

Rick
by rfincher1
Sat May 26, 2012 5:46 am
Forum: General discussion
Topic: big graphical Java app running on the Pi
Replies: 10
Views: 2578

Re: big graphical Java app running on the Pi

I have heard some accounts that JIT is not enabled for Arm V6 architecture. I can tolerate 700Mhz ARM11, but Java without JIT would be like running on a 70Mhz box. . From what I gather Open JDK doesn't unless you get it with Cacao. The Oracle embedded JVM uses JIT and is the fastest in the benchmar...
by rfincher1
Sat May 26, 2012 5:31 am
Forum: Beginners
Topic: First impressions - Slow, Scary & unfriendly
Replies: 212
Views: 44507

Re: First impressions - Slow, Scary & unfriendly

Maybe a strategy for living with the memory limits and still using Java is to write web apps that run under a Servlet container like Tomcat. Jetty has a pretty small memory footprint and a few others are even smaller. That way you off load all the user interface stuff to the browser on a remote mach...

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