Audio frequency generator: Difference between revisions

=={{header|ZX Spectrum Basic}}==

The ZX Spectrum is not very good at making sound. Most applications in BASIC would just produce annoying beeps, and the following is no exception. To emulate the signal generator, we just produce repetative beeps using the inbuilt speaker. The left and right keys (5 and 8) change the tone. There is no volume control on the Spectrum.

<lang zxbasic>10 REM The crappest signal generator in the world

20 REM We do not check for boundary errors in this simple demo

30 LET n=1

40 LET k$=INKEY$

50 IF k$="5" THEN LET n=n-0.5

60 IF k$="8" THEN LET n=n+0.5

70 PRINT AT 0,0;n," "

80 BEEP 0.1,n: REM beep for 0.1 second at n semitones relative to middle C

90 GO TO 40</lang>