Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site randvax.ARPA Path: utzoo!watmath!clyde!floyd!harpo!seismo!hao!hplabs!sdcrdcf!randvax!jim From: jim@randvax.ARPA (Jim Gillogly) Newsgroups: net.micro.pc Subject: Re: How to make PC beeps - Again Message-ID: <1726@randvax.ARPA> Date: Tue, 28-Feb-84 11:31:03 EST Article-I.D.: randvax.1726 Posted: Tue Feb 28 11:31:03 1984 Date-Received: Sat, 3-Mar-84 23:05:30 EST References: <2567@azure.UUCP> Organization: Rand Corp., Santa Monica Lines: 35 ---------- There's a beep routine in the ROM at location E666. It produces a beep at 896 Hz (by my computations) (as opposed to the 1000 Hz that the comments claim). It reads as follows: BEEP PROC NEAR MOV AL,10110110B ;SEL TIM 2,LSB,MSB,BINARY OUT TIMER+3,AL ;WRITE THE TIMER MODE REG MOV AX,533H ;DIVISOR FOR 896 HZ OUT TIMER+2,AL ;WRITE TIMER 2 CNT - LSB MOV AL,AH OUT TIMER+2,AL ;WRITE TIMER 2 CNT - MSB IN AL,PORT_B ;GET CURRENT SETTING OF PORT MOV AH,AL ;SAVE THAT SETTING1