From: Rhialto (rhialto_at_azenomei.knuffel.net)
Date: 2005-01-03 02:09:14
On Mon 27 Dec 2004 at 14:06:39 -0700, Rich wrote: > I recently acquired an 8032 and I'm looking for some code to drive the > peizo speaker with the VIA chip. Does anyone have a good starting > point? From what I've been able to determine you use the shift > register functionality on the VIA to drive the piezo speaker. I'm > guessing that you'd have a periodic interrupt routine to change the > shift register data/control in order to play the melody. Am I on the > right track? The common idiom is to 1. enable the shift register - poke 59467,16 2. set the desired wave form in the shift register - poke 59466,15 3. set the desired frequency (actually time between bit shifts) - poke 59464,whatever If you want to play some melody, you repeat step 3 periodically. Be sure to undo step 1 before using the tape recorder - poke 59467,0. I used to know these numbers off the top of my head, but I had to look them up this time. > Thanks! -Olaf. -- -- Ceterum censeo "authored" delendum esse. ___ Olaf 'Rhialto' Seibert --  Ugly English neologism. \X/ rhialto/at/xs4all.nl --  For lawyers whose English/Latin is below par. Message was sent through the cbm-hackers mailing list
Archive generated by hypermail pre-2.1.8.