Day 6

Reading an IBM 5081 card:

Punch cards, in general, were used earliest for controlling textile looms, operating musical instruments, but more modernly used for processing, input and data storage.

The IBM 5081 cards that we were given during class to read are actually the early forms of hard drives. It took me awhile to figure out what they were, but once I figured that out, I searched them on google and found a good wikipedia entry that helped me crack how to read the code. The url is:http://en.wikipedia.org/wiki/Punched_card

Here are my instructions on how to read a punch card (they may be very confusing!):

1. there is a key found on the wikipedia page that really helped me--here is what it looks like

     ______________________________________________
   /&-0123456789ABCDEFGHIJKLMNOPQR/STUVWXYZ
Y / x           xxxxxxxxx                
X|   x                   xxxxxxxxx        
0|    x                           xxxxxxxxx
1|     x        x        x        x
2|      x        x        x        x      
3|       x        x        x        x     
4|        x        x        x        x    
5|         x        x        x        x   
6|          x        x        x        x  
7|           x        x        x        x 
8|            x        x        x        x
9|             x        x        x        x
 |________________________________________________

2. From there I went along my punch card and tried to match up what was punched out with what I was given with this key.
3. I used another card to help me follow along so I wasn't constantly losing my place.
4. Remember to keep in mind was there are different sections of the card that are punched--y,x,0-9
      **numbers only had one punch (y-9)
      ** letters A-I had 2 punches (y and 1-9)
      **letters J-R had 2 punches (x and 1-9)
      **letters slash (symbol)-z had 2 punches (0-9)
5. After I slaved over my punches and trying to figure out what my card was saying, I realized that the code was in English at the top of the card.
6. The punches were given so that a computer could read the card and punch the punches, but the English was printed on the cards as well.