   1 .
   2 .
   3 .
  10 clear ;FC=0;BC=7
  15 NT=3
  20 print "  SELECT A WAVEFORM"
  25 print 
  30 print "  1.WAVE A"
  35 print 
  40 print "  2.WAVE A AND B"
  45 print 
  50 print "  3.WAVE A+B"
  60 if &(22)=16goto 10
  70 if &(23)=8goto 100
  80 if &(22)=8goto 200
  90 if &(21)=8goto 300
  95 goto 60
 100 gosub 400
 110 BC=0;FC=7;NT=0
 120 for X=-75to 75step C
 130 gosub 600
 131 CX=-75
 132 CY=40
 135 print #3,Y,#3,A
 140 box X,Y,1,1,1
 145 box X,-40,1,3,1
 150 next X
 160 goto 60
 200 gosub 400
 210 gosub 500
 220 for X=-75to 75step C
 230 gosub 600
 240 box X,Y,1,1,1
 250 gosub 700
 251 CX=-75
 252 CY=40
 255 print #3,Y,#3,A,#5,W,#3,B
 260 box X,W,1,1,1
 265 box X,-40,1,3,1
 270 next X
 280 goto 60
 300 gosub 400
 310 gosub 500
 320 for X=-75to 75step C
 330 gosub 600
 340 gosub 700
 351 CX=-75
 352 CY=40
 355 print #3,Y+W,#3,A+B
 360 box X,Y+W,3,3,1
 361 box X,Y,1,1,3
 362 box X,W,1,1,3
 365 box X,-40,1,3,1
 370 next X
 380 goto 60
 400 clear 
 405 print 
 410 print "  FOR WAVE A"
 415 print 
 420 input "  START WAVE AT ?"Y
 425 print 
 430 input "  WAVE LENGTH ?"A
 435 print 
 440 input "  STEP ?"C
 445 clear 
 450 return 
 500 clear 
 505 print 
 510 print "  FOR WAVE B"
 515 print 
 520 input "  START WAVE AT ?"W
 525 print 
 530 input "  WAVE LENGTH ?"B
 535 clear ;BC=0;FC=7;NT=0
 540 return 
 600 if Y>0A=A-1
 610 if Y<0A=A+1
 620 Y=Y+A
 630 return 
 700 if W>0B=B-1
 710 if W<0B=B+1
 720 W=W+B
 730 return 
>:return 
