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.

On the three-hour meeting of my Interfacing Computer Systems course on the second day of the fourth week of classes, I gave them the group “experiment” of simulating a seven segment display with pairs of LE diodes connected to seven of the eight pins of the parallel port.

This was to be controlled by a visual basic program with two buttons, one for increasing the single digit displayed, and the other for decreasing it.

Instead of constructing the module from scratch, I told them they could use the LED on and LED off program I showed them during the previous meeting.

I initially told them that the counting should stop at zero for the lowest and nine for the highest, starting with an initial value of five, until someone suggested that the numbers should loop.

The students had to learn how to declare variables globally and how to initialize them before any of the buttons were clicked.

They had to figure out what values to put in the arrays to be sent to the parallel port.

They had to determine whether to use a loop or not in their program, and how to go about reverting the nine back to a zero and vice versa.

They had to make a new circuit on the breadboard with a new value for resistance given that they now had either two diodes in series or two diodes in parallel running on the five volt sent from inside the computer.

For their grouping, I said at the start of the term that it would be flexible so that their odd number would not be unfair to those with fewer members if the groupings were permanent.

In the previous meetings, I had said those arriving first would be grouped together. At least two usual early arrivers joked with each other that one of them should be late in the succeeding meetings.

So this time I decided this to alternate the assignment, so that there would be at least two groups working as soon as at least one member each arrived.

How I will group them next time would have to be figured out when I cross that bridge in the next session.

I also told them that in the next meeting, they would now have to work with an actual seven-segment display, and just tweak their finished software and circuit accordingly.

Session 793 has reached one of the limits of its range of possible values here. Class dismissed.