Texas Instruments TI-99/4A User Reference Guide

Marquee
This program puts a marquee on the screen. The colors are
prnnllr:p:n r;mnnmly, ;mn ::l tnn~ snllnrls par.h timp a r.olor bar is
placed on the screen.
These statements clear the screen and assign each character set (2
through 16) to a different color. The RANDOMIZE statement
ensures that a different set of colors will be produced each time the
program IS run.
These statements produce a border for the marquee.
ThiS loop places color bars on the screen moving from left to right
(columns 3 through 30). Each time a bar is placed on the screen. a
tone sounds. The negative duration allows the sound to be cut off
and a new sound to begin each time the CALL SOUND statement
is performed. The subroutine beginning at line 310 generates the
random colors and tones.
This loop is the same as the loop in lines 200 through 240 except
that the color bars are placed on the screen moving from the right
to the left. These color bars are placed below those generated by
the previous loop, When the loop is finished, the program transfers
to line 200 to begin at the left again.
This subroutine generates a random character (thus also generating
a random color) for the CALL VCHAR statements (lines 220. 270)
The assignment statements in lines 320 and 330 generate a random
tone. The RETURN statement transfers the program to the
statement following the GOSUB (lines 210.260).
User's Reference Guide
Examples:
>NEW
>100 REM MARQUEE
;.110 flllNIlOMIZE
>120 CALL CLEAR
>130 FOR 5=2 TO 16
>140
CALL COLOR(S,S,SJ
>150 NEXT S
>160 CALL HCHAR(7,3,64,28)
>170 CALL HCHAR(16,3,64,28)
>1BO CALL VCHARt{,~,o4,10J
>190 CALL VCHAR(7,31,64,10)
>200 FOR A=3 TO 30
>210 GOSU8 310
>220 CALL VCHAR(8,A,C,4}
>230
CALL 50UND(-150,Y,2)
;>240 Nl:X I A
>250 FOR A=30 TO 3 STEP -1
>260 GOSU8 310
>270 CALL VCHAR(12,A,C,4J
7280 CALL 5DUND(-150,Y,2J
>290 NEXT A
>300
GOTD 200
>310 C=INT(120*RND}+40
>320 N=INT(24*RND}+1
>330
Y=220*(2h(1/12»AN
>340 RETURN
>RUN
--screen cLears
--marquee appears
(press CLEAR to stop
the program)
I1I.l7

Texas Instruments TI-99/4A Specifications

General

Brand	Texas Instruments
Model	TI-99/4A
Category	Desktop
Language	English