EOF - The Hardware Hacking Behind the Software Radio
A rotary encoder is a digital input device used to measure angular rotation and direction. It does this by sending two out-of-phase pulse trains. Direction is determined by which pulse arrives first. The pulses then can be counted to determine magnitude of rotation. There are many manufacturers and grades of rotary encoders. We used a unit by Bourns, part number PEC11-4225F-S0024. See the Radii home page for details on how to interface this encoder with a PIC.
When shopping for an LCD, first make sure it is HD44780-compatible. This is the most widely supported interface; anything else could slow down your efforts. The backlight type for the display is also important. Electro Luminescence—think Timex Indiglo—looks great but has unusual power requirements. The fastest and easiest way to go for backlighting is to use an LED backlit display. An LED backlight generally requires standard 5 VDC power. When shopping for an LCD with backlight, be sure to verify the type of backlight before bidding/buying.
The PIC interface levels are TTL-level outputs (that's transistor-transistor logic). With TTL, about 5V is on and about 0V is off. Interfacing this to RS-232/serial port (12V on/0V off) requires the use of a TI MAX232 dual-driver/receiver chip and a handful of resistors/capacitors. The chip does most of the work for you, but some assembly is required for the interface board and the serial cable used.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
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- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
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- Managing Linux Using Puppet
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- SuperTuxKart 0.9.2 Released
- Google's SwiftShader Released
- Parsing an RSS News Feed with a Bash Script
- Doing for User Space What We Did for Kernel Space
- Rogue Wave Software's Zend Server
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide