110
•You may define any position in the ASCII table except the control code area, but you cannot define more than 35 characters.
Photocopy the grid in Figure 7-3 to help design your new characters. We will use a tiny representation of a picture of an automobile for our example.
Next we calculate the vertical numerical values of the columns of dots, and enter them underneath the grid. Looking at Figure 7-4, we see that each vertical column (which has a maximum of 24 dots) is first divided into three groups of eight dots. Each group of eight dots is represented by one byte, which consists of eight bits. For example, looking at Figure 7-4, we see that in the left-most column there are five dots, and they are sitting in the “1” box of the 1st byte, “128”, “64”, “32”, and “16” boxes of the 2nd byte. Thus its vertical value is 1 for the 1st byte, 240 for the 2nd byte, and 0 for the 3rd byte.
ASCII code:
2nd
byte
Data 1% 2nd: 3rd:
4th:
3rd
5th:
byte6th: 7th: 8th: 9th:
Figure 7-3.Use thisgrid(oronesimilartoit)todefineyourown
draftcharacters.
