This program helps avoid mistakes when typing programs into a BBC Micro. It gives a short bleep when lower case letters are entered.
It differs from other programs of this type as it uses the keyboard vector OSRDCH leaving the 'events' vector free.
With OS 1.2, *FX 214,1 shortens the bleep, while *FX 212,216 or 212,232 softens it. The rest of the listing works with all versions of the OS. *FX210,1 turns all sounds off.
10 *K.10?&210=0:?&211=9:*FX214,1|M
20 VEC=!&210 AND &FFFF:IFVEC=&900 END
30 FOR P=0 TO 2 STEP 2
40 P%=&900:[ OPTP
50 CMP#(ASC"a"):BCC E
60 CMP#(ASC"z"+1):BCS E
70 LDA#7:JSR&FFEE
80 .E JMP VEC
90 ]:NEXTP
100 REM_RUN then press BREAK
19th January 1985
