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TangentAudio

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Everything posted by TangentAudio

  1. Sadly, no. I haven't even powered up any of my Atari stuff in well over a year. With so many things competing for my attention these days, it's been perpetually stuck on the back burner. No promises, but maybe I'll be able to get back to it this fall/winter, as that is when I usually get wrapped up in these kind of projects. cheers, Steve
  2. Outdoor activities have pretty much taken over my attention lately, which is great for the soul but bad for productivity on projects like this. I haven't forgotten about it, though, and still hope to get back to it when my free time and attention span allow! Hope everyone is enjoying their summer as well. -Steve
  3. Nothing to report, sadly. Between outdoor adventures and work being busy, it hasn't left much time for Atari stuff.
  4. True to his word, he sent me a spare, free of charge. Thanks for making AtariAge great, TT!
  5. Super generous individual! I posted about having a non-working Atari 8-bit cartridge and he shipped me a spare that he had, at his expense! This kind of experience is what makes AtariAge awesome.
  6. Printing is something I'd like to do eventually... Not sure when it will happen - still a ton of work to do to make this useful.
  7. Finally, it's actually doing something related to the project title... Just a simple test of everything so far, executing a command/response protocol over the PBI->SPI FPGA link to implement a few of the most rudimentary wifi commands like initializing and scanning. Just a quick demo that shows a scan with just my main two access points visible, then I turn on a test router and re-scan so a third one shows up.
  8. Ugh. I bought a 600XL from someone on Ebay that was packaged terribly. Power supply brick and 600XL - no bubble wrap, both loose inside of a crappy 1970s briefcase, which was tossed into a cardboard box with a little bit of bubble wrap (?!). Needless to say the 600XL showed up rather beat up. Space bar smashed off, scratches on the smoked plastic, scuffs and scrapes.
  9. Another aspect is why would some of us choose to spend so much of our time developing new software or hardware for a nearly 40 year old platform? Aside from the intrinsic enjoyment we get out of the experience (it's still fun, after all), there's a community element that adds to the enjoyment. Computers are somewhat unique in that they are a creative platform. Unlike some other forms of nostalgia and collecting, where it's all about simply obtaining an item and staring at it on a shelf once it's been obtained - these computers are still living platforms that can support new creations. I think there are many parallels to the classic car scene. Some people buy classic cars for some of the same reasons we enjoy collecting this old Atari stuff - to connect to their younger times. Classic cars, like our computers, are simpler to understand and work on. Most classic car scenes have people who put their skills to use making new products that help keep the old cars running or bring touches of modernity to them. Enthusiasts still spend their time and money tinkering on these old cars, going to weekend meets and shows, etc. Yet, I suspect most classic car enthusiasts drive something modern and practical as their daily driver. A major difference is that cars are, in North Americal culture at least, worshiped. Computers do not enjoy the same sort of status in our society, but the patterns of behavior surrounding the hobby are very similar in my opinion.
  10. To say most of us are "still using" our Atari 8-bits is a bit misleading. I assume most people tinker with them as a hobby, but aren't using them for serious day-to-day use. Sure, there are probably some exceptions, but by and large these machines are a curiosity, a novelty, and a nostalgic touchstone that connects us to an earlier, simpler, more fun time in our lives. In 1984, the 800XL was my first computer, and ultimately it was the platform that launched me into my career in software and hardware engineering. I've found a lot of joy in reconnecting with those old memories, and through the process of developing a modern WiFi PBI peripheral for the A8, both literally and figuratively bridging the past and the present. Filling in the gaps in my understanding of the technical details of the platform has been interesting, and it has allowed me to appreciate the architecture and design of the system from an entirely different perspective. When I was a teenager I defended the Atari from a highly emotionally charged place - it was the only computer I had, and I defended it tooth and nail. Now, removed by 25+ years, and with the benefit of a lot of study of other contemporary systems of the day, it's much easier to appreciate the Atari from an objective standpoint and see both the computer and the various incarnations of the Atari company for what they really were - and understand them in the proper historical context. Interestingly, this does not diminish the nostalgic value for me. I was concerned it might spoil the 'magic' that surrounded the system, but somehow learning more details has not diminished the warm memories I have. Any computer platform is, in essence, a world unto itself. The myriad of design decisions that led to the final product created a unique world that each of us has inhabited at different levels - from simply enjoying programs and games on the system to living deep down in the 1's and 0's by programming the system or making hardware for it. By nature of these systems being so much simpler, their design was influenced by a relatively small number of people. I have found that this is one of the contributing factors to giving the classic machines so much more personality than the bland systems we have today. This is certainly a piece of what makes them still enjoyable to appreciate even all this time later.
  11. Bits and pieces. I put some hours in over the weekend doing some boring work towards getting the handshaking working, which is a combination of FPGA work, and code on both the Atari and ESP32. I also put some time in on the schematic, inching that closer to being ready for a PC board layout. As I knew would happen with the arrival of nice weather, I'm spending more of my free time outdoors and haven't been as available to put in long hours down in my lab... but I am hoping to keep the project moving forward over the summer, even if it goes slowly.
  12. I picked up a Touch Tablet full package for pretty cheap on Ebay, and it came with everything including the AtariArtist cart. Unfortunately I can't seem to get any life out of it whatsoever. Cleaned the contacts with DeoxIT D5, reflowed every solder connection, checked continuity on all traces, and tried in a couple different computers... nothing. Computer basically behaves like there is no cart installed. I can boot to DOS and try 'run cartridge' and get "No cartridge" back. First time I've ever seen a cart failure like this, anyone else experienced this? I suppose it could have been used in an Atari with a failed power supply and the PROMs could be toast from over-volting, but I can't come up with many other likely scenarios. I was able to find AtariArtist in ATR form and test out the tablet, but I'd still like to have a working cart for my collection. If I got ambitious I suppose I could just make one with EPROMs, but I'm not sure I'm that motivated.
  13. Any chance you have a stock 400 membrane keyboard you don't need? I picked up a 400 this week but it came with an aftermarket keyboard - looking to make it stock for nostalgia since the first Atari I used was a 400, terrible keyboard and all.
  14. You'd be surprised, USPS Priority Mail for larger/heavier packages is not cheap. An XEGS+XF551+accessories, disks, carts, power supplies, etc. was like $56 to ship. 1200XL by itself with no PSU was $35, same for a 400 - no power supplies on either. *edit: I see that ebay listing was for economy shipping - that does seem steep!
  15. I am restoring a 400 and looking for the stock membrane keyboard in clean and working condition.
  16. That's OK, I am not initially intending this for XEGS. It's going to start out as an external PBI (and probably ECI) device. I've had some daydreams of rolling in a lot of the functionality of a SIDE2 and a U1MB+ and making an internal upgrade, but that would be down the road.
  17. Damn, this document is amazing. Thank you, Avery!
  18. Could apply the technique I am using in my PBI WiFi design, using dual port RAM in an FPGA. One could probably design a nice math coprocessor in an FPGA and have it operate on sections of memory mapped to the Atari. Just needs a little bit of handshaking to signal back and forth that data is available or locked.
  19. I adopted this 1200XL from rdea6 - tested and still working after making the cross-country trek.
  20. Changed /EXTSEL (and /MPD for good measure, even though it seemed fine only being active with PHI2=1) to simple combinatorial logic and it's all good now. My ANTIC/SPI-DMA/Dual Port RAM passthrough test now works without pre-filling the Atari RAM with FF's. Another good catch, it's good to have another set of eyes helping. Thanks!
  21. This seems the most likely, since I just pulled it up on the scope and it seems I am only activating it on the latter half of the bus cycle when PHI2=1 ... I'll have to fix the VHDL.
  22. I'm still hoping to integrate some form of printing into the R:Fi project, though I don't know exactly what form it will take. (I guess that might make it a P:R:Fi .. or D:P:R:Fi once it has disk capability... Need a better name.)
  23. Here's a schematic of the RAM, MMU and decode logic that I drew up. It was partly an exercise to follow through the logic myself, and also partly to create a nice little one page reference for future use. 800xl_ram_mmu_decode.pdf
  24. I did find a source for the MMU logic, thanks to some work in the past by Bob Woolley. My theory above doesn't make much sense now that I've looked at the schematic again after a cup of coffee. Of course /EXTSEL=0 should inhibit /CAS regardless of the state of EXTENB, so it doesn't seem likely U1MB+ or anything else is an issue, and I probably have something screwy on my prototype. What seeing this logic possibly does help confirm is why I have proper functionality in the D800-DFFF window even if I may have a non-functional /EXTSEL on my board. It looks like the EXTENB logic includes D800-DFFF, so it's entirely likely the MMU has actually been the thing inhibiting /CAS for D800-DFFF, all the while masking an issue on my prototype until I started testing outside of that window. I'll go hunting tonight and I bet I will find a dumb wiring error. This contains a version of the 800XL PAL logic in PALASM, at least Bob's interpretation of it. I've been redrawing this part of the 800XL schematic to make a nice little one page quick reference, and I'll include the equations in the MMU portion. Name 800XL MMU; Partno CO61618; Date 02/25/99; Revision 00; Designer Bob Woolley; Company Atari Rulz!!; Assembly 1200XL; Location U14; Device P16L8; /******************************************************************/ /* Stock Atari XL/XE MMU */ /* */ /* */ /******************************************************************/ /* Allowable Target Device Types: 16L8 */ /******************************************************************/ /** Inputs **/ Pin 01 = A11 ; /* address bit 11 */ Pin 02 = A12 ; /* address bit 12 */ Pin 03 = A13 ; /* address bit 13 */ Pin 04 = A14 ; /* address bit 14 */ Pin 05 = A15 ; /* address bit 15 */ Pin 06 = MAP ; /* PB7 diagnostic bit */ Pin 07 = RD4 ; /* right cart. @ $8000-$9FFF */ Pin 08 = RD5 ; /* left cart. @ $A000-$BFFF */ Pin 09 = REN ; /* PB0 OS ram enable */ Pin 11 = REF ; /* DRAM refresh */ Pin 14 = MPD ; /* Math Pack Disable */ Pin 18 = BE ; /* Basic Enable */ /** Outputs **/ Pin 12 = !S5 ; /* left cart. select */ Pin 13 = !BASIC ; /* Basic ROM select */ Pin 15 = !OS ; /* OS code select */ Pin 16 = !CI ; /* DRAM CAS inhibit */ Pin 17 = !IO ; /* I/O select @ $D000-$D7FF */ Pin 19 = !S4 ; /* right cart. select */ /** Logic Equations **/ /** # is or **/ /** ! is not **/ S4 = !A13 & !A14 & A15 & RD4 & REF;/* RD4 and addresses $8000-$9FFF */ S5 = A13 & !A14 & A15 & RD5 & REF; /* RD5 and addresses $A000-$BFFF */ IO = A12 & !A11 & !A13 & A14 & A15 & REF; /* addresses $D000-$D7FF*/ CI = !A13 & !A14 & A15 & RD4 & REF /* right cart. */ # A13 & !A14 & A15 & RD5 & REF /* left cart. */ # A13 & !BE & !A14 & A15 & !RD5 & REF /* BE and $A000-$BFFF */ # OS /* OS addresses */ # A12 & !A11 & !A13 & A14 & A15 & REF /* I/O addresses */ # !REF; /* memory refresh */ OS = A13 & A14 & A15 & REN & REF /* addresses $E000-$FFFF */ # !A12 & !A13 & A14 & A15 & REN & REF /* addresses $C000-$CFFF */ # A12 & A11 & !A13 & A14 & A15 & MPD & REN & REF /* addresses $D800-$DFFF */ # A12 & !A11 & !A13 & A14 & !A15 & !MAP & REN & REF; /* addresses $5000-$5800 - mapped */ BASIC = A13 & !BE & !A14 & A15 & !RD5 & REF; /* BE and $A000-$BFFF */
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