Commodore Plus 4 - Page 61

BASIC Version 3.5 Commands, Functions, and System Variables 49
Partial Headering
You can also clear a disk directory on an old disk without formatting the disk.
This procedure, which gives you an empty disk with the old id, is called a partial
header. Omit the id code from the HEADER command to do a partial header.
Note: The drive and unit number parameters and the disk name can be
specified with a variable or expression in parentheses.
Examples: HEADER "CIRCLES",D0,IG3
HEADER 'a:KrSIJRANCE//,Dl,IP5
HEADER "HOUSEFILES",DO Performs a partial header.
HELP Abbr. heL
Highlights an erroneous command in a BASIC program by putting the com
mand in flashing mode. If you want to highlight the error in a line, use HELP
after the computer displays an error message when you execute a program. The
HELP function key is defined with this BASIC command.
HEX$ Abbr. hE
HEX$ (number)
Gets the hexadecimal value for the decimal number in parentheses as a four-
character text string. The value of the number in parentheses must be between 0
and 65535 inclusive. Since the hexadecimal value is always printed as a four-
character string, zeros are placed at the beginning of values that are less than four
characters long.
Note: The HEX$ function accepts only nonnegative input. To use 16-bit two's
complement input, use
X$ = HEX$(X-(X<0)*65536)
Example: PRINT HEX$(45), HEX$(S001)
002D 07D1
IF ... GOTO ... ELSE Abbrs. if/gO/eL
IF logical value GOTO line number : ELSE commands
Branches the program based on the value of a conditional clause. IF is a
compound conditional statement that checks the status of a condition in the
command and then chooses one of two courses of action.
One of the two IF command options is stated in the GOTO clause, which is
executed when the IF condition is true. When the IF condition is false, the GOTO