Reply 80 of 91, by Great Hierophant
Is there any Documentation how the DAC works ? :) […]
Is there any Documentation how the DAC works ? 😀
Ahh i see..
These two activate the IBM PS/1 Audio Card. It is always situated at ports 0200, 0202-0204, so there's no need for a "base" value.
is it dma driven ? or more like a covox device ?
It's an in-between, think of it like a more capable Disney Sound Source. it uses a 2K FIFO buffer for the DAC and can send an interrupt when the buffer is almost empty. The rate in which the FIFO is sent to the DAC is controlled by an 8-bit timer. The Options from the Technical Reference will tell you how it works : ftp://ftp.mindcandydvd.com/pub/drivers/IBM/PS … 2011/index.html
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