Commodore 16 User Manual page 72

SSHAPE "VARIABLES", 0, 0
Saves screen area from the upper
left corner to where me cursor is
positioned under the name
VARIABLES.
GSHAPE "VARIABLEr„,1
Displays VARIABLES shape with
background and foreground colours
reversed, with the too lett of tne
shape positioned at the cursor.
SYS
SYS address
TRON is used in program debugging This statement begins trace
mode. When you are in trace mode, as each statement executes, the
line number of that statement is printed.
f I
'
TRAP
TRAP fline41
When turned on. TRAP intercepts all error conditions (including the
7lUIV1ITOP key) except "UNDERD STATEMENT ERROR" In the event
of any execution error, the error flag is set, and execution is transferred
to the line number named in the TRAP statement. The line number in
which the error occurred can be found by using the system variable EL.
The specific error condition G contained in system variable ER. The
string function ERRS(ER) gives the error message corresponding to any
error condition ER.
NOTE: An error in a TRAP routine cannot be trapped. The RESUME
statement can be used to resume execution. TRAP with no MO'
argument turns oft error TRAPping.
TRON
TRON
EXAMPLES
STOP
STOP
This statement halts the program. A message. BREAK IN LINE A',
where the
4'
is the line number containing the STOP. The program can
be re-started at the statement following STOP It you use the CONT
command. The STOP statement is usually used while debugging a
program.
TROFF
TROFF
This statement turns trace mode off.
The word SYS is followed by a decimal number or numeric variable in
the range 0 to 65535. The program begins executing the machine
language program starting at that memory location. This is similar to
the USR function, but does not pass a parameter. See the
Programmer's Reference Guide for information about machine
language programs.
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