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 second lecture in Computer Architecture for the second week of the third trimester, all I was able to take up was the addition and subtraction of signed binary numbers in two’s complement format.

This is because the students, being very, very comfortable with me since I was first their teacher two years ago, were always interrupting anytime they did not understand anything, which was often, considering they apparently have very little retention from the previous lessons, they are always distracted when I’m in the middle of an explanation so they don’t catch the important points, and they show up late.

Admittedly, I did not have that much time to introduce the two’s complement format of signed binary numbers last meeting either, and I didn’t write down a lot of the concepts and procedures.

Somehow, since I had the assumption that most of the discussion I have at least for this part of the course outline should already be familiar to them, I do not bother writing down the salient points on the board.

This time though (but only after several complaints) I made a table on the board listing down all the binary numbers with four bits, their conversion to unsigned decimal (which we took up during the first lecture), to signed decimal in sign-magnitude format and in two’s complement format.

Thus it should have become evident to them that for binary numbers whose lead bit is zero, the representation in all three of the columns mentioned above are the same, and they only differ when the lead bit is one.

Maybe I should also have assured them that in the test, I would always mention to them which of the three formats mentioned they are converting to or from.

Another thing that may have made the operations confusing was that I performed it both in decimal and in binary, instead one first and verifying the result in the other.

At least I was able to draw class participation through the board work of one particular example at the end of the class.

Session 949 reads zero in any converted number format. Class dismissed.