chjmartin2
Experienced Member
- Joined
- Dec 26, 2012
- Messages
- 424
Since this stuff is a bit Tandy specific, what about a small memory expansion card that filled in upper conventional RAM - the same RAM the video controller is scanning from. Then add an IDE interface to that with on-board DMA. It would be cheating, but the first design iterrations I did for JR-IDE (on paper) did just that. The DMA transfer loop, lane steering, and latch logic fit in an ATF1508. The 1MB RAM was organized in 16 bits with two parts on the back of the pld along with the IDE header. Block transfers to an on-chip address target could run as fast as any modern IDE device supports with an independent clock. Again.. cheating but a thought. It would still use the on-board video for output.
Wow... complex... My goal would be to get a "stock" Tandy 1000 TL. I use the word stock because I will use an XT-IDE only because I do not have another mass storage solution. Were there any hard drives that maxed out the ISA bus at that time?