void setup(){
  pinMode(13, OUTPUT);
}
 
void loop(){
  digitalWrite(13, HIGH);
  delay(500);
  digitalWrite(13, LOW);
  delay(500);
}

First, we configure pin 13 for output by setting a bit in Data Direction Register B. Then we turn pin 13 by setting its bit in PORTB. Then we delay 500 milliseconds by marking the current value of timer0, converted into milliseconds, and letting the counter be incremented repeatedly at each clock cycle and overflowed into ever larger holders until the new value of timer0 represents an elapsed time of 500ms. Next we set the bit for pin 13 in PORTB low to turn the LED off. We do the delay dance again and we're home.

"I'm particularly interested in introductions for non-experts to subjects like biology, physics and astronomy, but I thought that opening up the question as broadly as possible would make it most interesting to me and other readers, especially as a future reference-point. I am thinking of books like "Mathematics for the Million", which made math accessible to a great deal of people."

'The goal of Linked Data is to enable people to share structured data on the Web as easily as they can share documents today. The term Linked Data was coined by Tim Berners-Lee in his Linked Data Web architecture note. The term refers to a set of best pra

"Streetcars -- which we define as rail transit vehicles designed for local transportation, powered by electricity received from an overhead wire -- differ from both buses and Light Rail. Streetcars can be modern, Vintage (antique) or Heritage reproduction) vehicles. All around the country, cities are building new streetcar lines. The most successful are tied in closelywith the local transit system."

"Technical Library At RPR, we're great believers in not reinventing the wheel. Consequently, one of our most rewarding pursuits is collecting technical books and documentation from the golden years of the railway industry, with special emphasis on early 20th century U.S. electric railway subjects. Our library directly supports our consulting work in many ways, providing hands-on technical information that is still relevant today, and also documenting the evolution of the industry. By illuminating the past, our library helps us keep today's projects in perspective. Our library is by no means the most unique or the most comprehensive, but we have enjoyed building it over the years, and we're always on the look out for new titles to add. The listing is presented here as a resource to others. We hope that those of you with similar interests might spot some new titles to look for, and we also hope that if you have electric railway titles that are not on our list, you'll contact us. In cases where no copyright issues exist, (applicable to many of the books here due to their age), it is also practical to exchange electronic copies or ordinary photocopies. We're working more and more with scanned documents, and expect this to continue to be a growing avenue for exchanging technical data. From time to time, we also acquire duplicate copies, and these are occasionally available for sale or trade. The books are grouped into a couple of major categories, and listed alphabetically. The left hand column contains a reference number for original copies in our library. We also collect periodicals such as Electric Railway Journal, and publications such as the Car Builder's and Locomotive Builder's Cyclopedias, but these are fairly common items and as such are not listed here. We hope the list is of "