Reply 60 of 114, by Great Hierophant
The best technical information available for the PSSJ can be found in the Tandy 1000 TL (or SL) Technical Reference Manual. You can find them here : ftp://ftp.oldskool.org/pub/tvdog/tandy1000/documents
There is also a document called TANDAC.DOC which helps explain how to make the DAC work I have attached it.
One thing I realized that in PSSJ Tandys, the DAC uses C4-C7. In non-PSSJ Tandys, those addresses would be mirrors of C0. However, it is important to note that the DAC adds another whole layer of complexity to the design because it uses an IRQ and a DMA. It also provides additional functionality to the sound generator. This functionality may never have been used by games. Also, there are BIOS calls added for the TL/SL and later machines to allow access to the DAC.
I would suggest that it would be much easier to use a Sound Blaster to emulate the Tandy DAC.
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