Student "edition" found at {csi dot journalspace dot com}.

Maybe I shouldn't have started this blog now, not with everything that's been going on.

In my two-hour Interfaced Computer Systems meeting for the fourth week of classes this second term (the same one I mentioned at the end of today’s post in the student edition) I finally arrived at the decision that if we could not make the parallel port accessible – at least as output – in C++ programming language, then we would have to resort to Visual Basic.

Good thing I had several examples that we were able to learn from, and I just used those to show the engineering juniors how to translate the commands into the ones they are familiar with in C++.

Although, for most of them who took up Advanced Computation Methods in the first term of the previous school year, Visual Basic is not a first time experience.

The simplest program I showed them was the one that asked for user input between 0 and 255, and sent that out to the data port address. It did not have any error checking, but we’ll get to that soon enough. It did, however, show the students that in VB it is possible to have the display statement and the declaration and the assignment to a variable (in other words, write and read) in one line.

Besides that they saw the simplest type of form, which just has changeable captions and no “okay” button, as well as the built in decimal to hexadecimal converter.

I also had to tell them several times in answer to their question that the 888 address assigned to the port memory location was the same as 378 in hexadecimal that I told them about before.

I also had to explain what a private sub was.

The second type of program was the one with two buttons: one to turn all the LED pins on and another one to turn all of them off.

I used this example to show them how to connect subroutines to objects and actions, as well as how to change the values sent to the output port.

The third sample program had a command button, and a program with a loop, the first one they encountered in VB (or so their spotty memory tells them). That’s why all their questions were concentrated on all the potentials of the for-loop, including decrementing values and having a step other than one.

The last program used an array and its dim declaration, which I used as a springboard to their exercise, that of a Knight Rider display simulator.

Session 789 also had to change programming languages at this point. Class dismissed.