Last visit was: Sat Jul 13, 2024 9:29 am
It is currently Sat Jul 13, 2024 9:29 am

 [ 1 post ] 
 OT: extreme programming on the 8088 for audio 
Author Message

Joined: Wed Jan 09, 2013 6:54 pm
Posts: 1789
This article explains how to use macros, self-modifying code, cycle-counting and data on the stack to play four channel music on the one-bit speaker of a 1981 PC. (Interrupts must be disabled to avoid jitter: so I think this pushes all the buttons for items of interest.) ... -its-done/
"there's 3 layers of code here: the actual 8088 mixer code, the v-instruction code in the stack and the h-instruction code interspersed into the song data"
Oh, and watch out for patching instructions which are already prefetched - the old version will execute.
"Debugging is still tricky, though - breakpoints don't work so well when your entire program is executed from the same 15 byte memory region!"
The player cuts in at about the 6m35s mark of the demo video - prior to that it's all beeps:

Fri Apr 10, 2015 6:03 pm
 [ 1 post ] 

Who is online

Users browsing this forum: CCBot and 0 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
Designed by ST Software