Game 4 Unit 5 of 6 1 hr learning time

The Signal

The whole screen flashes red — PAPER as a signal, not decoration — and BEEP marks every beat: the rising bar, the flash, the verdict.

83% of Reflex

The bar fills, then "NOW!" prints — and text is a weak signal. The eye takes a moment to read a word. A reaction test wants something faster and louder: the whole screen changing colour, and a sound on every beat. You changed PAPER and rang BEEP in Meet BASIC; here they stop being demonstrations and become the signal itself.

  10 BORDER 0: PAPER 0: INK 7: CLS
  20 RANDOMIZE
 100 CLS
 110 PRINT "Get ready..."
 120 PRINT
 130 PLOT 26, 90: DRAW 204, 0: DRAW 0, -6: DRAW -204, 0: DRAW 0, 6
 140 PLOT 28, 88
 150 DRAW 200, 0
 155 LET e = INT (RND * 140) + 88
 160 FOR x = 28 TO e
 170 PLOT x, 87
 180 BEEP 0.01, 10
 190 NEXT x
 210 PAPER 2: BORDER 2: CLS
 220 BEEP 0.05, 30
 230 LET t = 0
 240 IF INKEY$ <> "" THEN GO TO 270
 250 LET t = t + 1
 260 GO TO 240
 270 PAPER 0: BORDER 0: CLS
 300 PRINT "Your time: "; t
 310 PRINT
 320 IF t < 5 THEN INK 4: PRINT "Lightning!": BEEP 0.1, 20
 330 IF t >= 5 AND t < 15 THEN INK 5: PRINT "Quick!": BEEP 0.1, 15
 340 IF t >= 15 AND t < 30 THEN INK 6: PRINT "OK": BEEP 0.1, 10
 350 IF t >= 30 THEN INK 2: PRINT "Slow...": BEEP 0.1, 0
The entire ZX Spectrum screen and border flashed solid red
The signal: the whole screen turns red. No text to read — react to the colour.

PAPER as event, not background

In Story Builder and Oracle Stone, PAPER set a background colour that stayed put for the whole program. Here it changes during the run. Line 210 — PAPER 2: BORDER 2: CLS — repaints the screen and border red in an instant; the CLS is what makes the change fill the screen. That flash replaces the old "NOW!" text entirely: the colour is the signal, and a colour change registers faster than any word. Line 270 then sets everything back to black for the result. White, red, black — three states, each one telling the player where they are.

Sound on every beat

BEEP duration, pitch is back from Meet BASIC, doing three jobs at once:

  • Line 180 sits inside the fill loop — a tiny BEEP 0.01, 10 per pixel, so the bar rises with a ticking drone that builds tension as it climbs.
  • Line 220 fires a sharp BEEP 0.05, 30 the instant the screen flashes — the audible half of the signal.
  • Lines 320–350 each end with a BEEP whose pitch matches the verdict: high and bright for "Lightning!", low and flat for "Slow..."

Sight and sound now move together. The bar ticks as it climbs, the flash cracks, the verdict chimes — every moment that matters has a picture and a sound behind it.