Typing in numbers Whenever a number is to be entered on the command line as a parameter to an inbuilt command there are three ways of representing it: Decimal numbers are entered by preceding them by a full stop ‘ . Binary numbers are entered by preceding them with a ‘ % ’ symbol. Hexadecimal numbers are entered without any leading character. Decimal numbers may be preceded by a minus sign, eg.
.-1234 As an example, the command mfb 4000 .17000 %101011 will fill the memory range 4000 hexadecimal (16384 decimal) through 17000 decimal with the binary value 101011 (decimal 43) (assuming you have some reason to want to do this!) Numeric commands Most commands have as their arguments filenames, or numbers. Try the inbuilt expression calculator (a poor man’s pocket calculator) expr .23 + .84 - .29 If you don’t agree with the answer, note that you must put a ‘ . ’ and mathematical operators in front of decimal numbers when entering them, and must leave spaces between all arguments. The answer is given in binary, decimal and hexadecimal.
Check the values of different base number with the inbuilt base . base 40 .60 %100100 This command converts a set of numbers into hexadecimal, decimal (indicated by the . in front), binary (shown with % in front) and in addition, to octal. If you don’t know about different base number systems, you can read up on them in many computing and math text books. You should also note that these commands only work with integer numbers. That is, you can’t use numbers that include a fractional part, or a decimal point.
Special characters The semicolon character ; is used for putting comments on command lines (particularly within shell files, see below); any characters occurring after a semicolon are ignored. If the first non-blank character in a line is a semicolon, then the entire line is ignored. Use this method to remind you what a line is supposed to do. If you actually wish a semicolon to appear on the command line, rather than using it to indicate a comment, it will have to be surrounded by double quote ( " ) char- acters. For example, note the difference between the two examples of the inbuilt echo command, which merely repeats its arguments Command Handling User Tutorial Manual Page 23