Sharp MZ-800 - Page 179

Error processing statements
ON ERROR ON ERROR GOTO If an error occurs during program execution, this is a sentence saying
GOTO 1000 to jump to statement number 1000.
IF ERN IF ERN=43 THEN If the error number is 43, this is a command to jump to statement
1050 number 1050.
IF ERL IF ERL=350 A command to jump to statement number 1090 if the error statement
THEN 1090 number is 350.
IF (ERN = 43)* A command to finish the program if the error number is 43 and the
(ERL = 700) THEN error statement number is 700.
END For the BASIC, if an error occurs during the program, the error
number and error statement number will be set, respectively, to varia-
bles ERN and ERL.
RESUME 650 RESUME Transfers control once again to the command generating the error.
700 RESUME Transfers control to the command following the command generating
NEXT the error.
750 RESUME 400 Transfers control to statement number 400.
800 RESUME 0 __ Trasnfers control to the program heading.
Substitution statement
LET LET A=X+3 Substitutes sum results of numerical variable X and numerical data 3
to numerical variable A. LET can be omitted.
Input/output and colour control statements
COLOR 10 COLOR,,,2 Changes all screen background colour to red.
20 COLOR 3,2,7 Changes the colour of characters at coordinates (3,2) to white.
30 COLOR 4,2,4,2 Makes the colour of characters at coordinates (4,2) green, and the
background colour red.
PRINT 10 PRINT A Displays the content of numerical variable A on the CRT display.
?AS Displays the content of string variable A$ on the CRT display.
100 PRINT [6,5] Writes the ““ABC’’ string in yellow on a light blue background.
“ABC
110 PRINT [,4] Writes the ‘‘DEF”’ string in yellow on a green background.
“DEF”
120 PRINT [7,4] | Writes the ““GHI”’ string in white on a green background.
“GHI"
200 PRINT New line if PRINT only.
PRINT USING PRINT USING ‘# A designation which lines up decimal point positions by a fixed
HAAR GA decimal point display.
INPUT 10 INPUT A Inputs values relative to variable A from the keyboard.
20 INPUT A$ Inputs strings relative to string variable A$ from the keyboard.
30 INPUT Before input from the keyboard, the question string data VALUE? is
“VALUE?”;D displayed. The semi-colon is used to separate the string from the
variable.
40 INPUT X, X$, Numerical variables and string variables can be combined by using
Y, ¥$ the comma (,) to separate them, but it is necessary to match the type J
of variable at the time of input.
SET SET 30,15 Iluminates the position of coordinates (30,15).
RESET RESET 30,15 Erases the position of coordinates (30,15).
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