“It ain’t dead till we say it’s dead.” Typical movie quote, but it is a reality that should be a good maxim. The parallel port printer per say is not used any more, but who says we can not still use the technology in some new way. Came across this article about using old hp Jet directs as home automation controllers. Supposedly you can get them on ebay for around ten dollars. Though you might have to add ten or twenty dollars in parts, it is still a bargain compared to the hundreds of dollars you have to spend with equipment from a company like Insteon. There are tons of articles where you can get information about using the Jet Directs for home automation. The one that started it all off was probably from Doktor Andy. Later it was expanded on from this article: Print server power control hack. I am even working on one of my own. Have another article about interfacing the parallel port add-ons. See: External device control (i.e. coffee machine).
Debian Linux in the latest update seems to have killed sound support. The forums have been temporarily closed citing some server issue. Hope there is a fix soon. Changed out the sound card and was able to get things working. Seems to be a cut in hardware support. Same thing happened with the wifi cards…..
Computers are getting smaller and smaller. We use them to solve problems, but you still have to give them instructions to do what you want. Computer languages are a way to give the computer the instructions you want it to use. The first computer I ever used was at college. Then they did not even have a computer major. Mostly you majored in math. The first computer was large and bulky. We used punch cards to get computer code into the machine. In fact, we used a language call Fortran (Formula translation) which was the forerunner of a more recent language called Basic (Beginner’s all purpose instruction code). Fortran is still actually around and you can still use it. On Linux it is sometimes called gfortran. Basic has evolved into so many variations that are too many to mention though you may have heard of VB.net. Personally I prefer Quickbasic variations for my non-gui systems.
The next computer I used in the Professional world was the Datapoint Terminal in the days of Arcnet networking. After studying Cobol and RpgII in going back to school years later earned a job working as a maintenance programmer using Databus (now called PL/B) and using RpgII (now RpgIV). Learning Databus was almost like being in a foreign county. But picked it up quickly. Thank god no more punch cards. You could work at a terminal. The first decrease in size. I had an old Datapoint 8200 computer to work on like this one:
To use a computer, you really had to work for a company. Then the microcomputers started to come out such as the Commodore 64. You could use a tv as a terminal screen, which really cut down on the costs. I remember working in a computer store as a consultant and I did programs for people. Even had to write a few programs for myself to solve problems of moving client files from one computer to another. Each system had it’s own format. Now a days we do not even have to think about moving data from one system to another with the internet. The first real computer I bought was a Commodore 64. One of the great pleasures was learning 6510 assembly language programming in person from the late great Jim Butterfield. Forgotten most of it now. Getting sort of getting smaller again.
Back to a little bit bigger, I used a personal computer from IBM and various computer manufacturers such as Dell. At that time I was teaching computing more than programming, though I did enjoy teaching budding programmers about the introduction to computing and programmer logic. Eventually I worked in computer support for a college. We used thousands of computers of various architectures and operating systems. Even became heavy into networking. You always were learning something new. From Novell, Microsoft, Apple, and then eventually Linux. Computers are more powerful but smaller.
Now things are going to take a turn for the smaller. The computers we have looked at so far were generally called complex instruction set computers. In the need to get smaller, reduced instruction set computers (aka risc) have come out to supplement the more powerful machines. Some of the Arm processors or the computer brains have become very popular. In fact, I had what was known as a Cisco Linksys Nslu2 that was used as a popular NAS (network addressed storage) device. Since it had a real cpu (risc), someone came up with a way to install the Debian linux operating system on it. My brother dared me to install it. Yep did it. Eventually wrote a program or two in C (made famous by Kernigan and Ritchie). Was able to use it as a web, music, file and etc server. It was worth it’s weight in gold. Though it seems pretty small you have not seen anything yet.
The only short coming to the Nslu2 was it did not have a terminal to type into so you had to access it remotely. You can purchase net tops that use the Risc cpu structure with the terminal attached. Just a little history to whet your appetite. Like I said, we have not seen anything yet. Now you have the tablets and smart phones. Dick Tracy watch here we come.
Simple survey of computer languages:
Just a little language comparison between Basic and Bash.
write a blank line write a title about the program write a blank line get the temperature from the keyboard write the result write a blank line
Temperature conversion from Centigrade to Fahrenheit.
echo echo "Temperature conversion from Centigrade to Fahrenheit." echo read -p "Enter degrees in Centigrade: " c let f=$((($c*9/5) + 32)) echo "Temperature in Fahrenheit is: $f" echo
print print "Temperature conversion from Centigrade to Fahrenheit." print input "Enter degrees in Centigrade: ",c f = (c * 9 / 5) + 32 print "Temperature in Fahrenheit: ";f print
Notice both seem to follow our pseudocode.
Fahrenheit to Centigrade code.
echo echo "Temperature conversion from Fahrenheit to Centigrade." echo read -p "Enter degrees in Fahrenheit: " f let c=$((($f - 32) *5/9)) echo "Temperature in Centigrade is: $c" echo
print print "Temperature conversion from Fahrenheit to Centigrade." print input "Enter degrees in Fahrenheit: ",f c = (f - 32) * (5/9) print "Temperature in Centigrade: ";c print
Sometime you might have to make cd without the use of the mouse. Making a data cd from the command line.
Make a temporary directory to hold the files
$ mkdir tempiso
Copy all the files you need to the temporary directory
$ cp source_files tempiso/.
Make the iso file to write (mkisofs -f -R -r -l -J -Vvolumename -Avolumetitle -Pcreatorname -o cd.iso cd/)
$ mkisofs -f -R -r -l -J -Vwintools -Awinprogs -Pme -o win.iso cd/
Which creates the win.iso file and then you need to write that file to the cd.
$ cdrecord -v dev=1,0,0 win.iso
$ cdrecord -v /dev/sr0 win.iso
Viola, you have your data cd. This can ge really important if you are remotely accessing system. You can then ssh the iso to your system for writing to your local cd/dvd drive.