FDOS Posted March 28, 2020 Share Posted March 28, 2020 ONLY the REAL thing will do, and hopefully at a reasonable price. I've been continuing development of TI BASIC PLUS (TIB+), using an EA Supercart, as the RAM banks on my MG 80K GramKracker don't work (I believe it's a switch problem rather than RAM). I'm sure most of you know that I can no long solder due to hands & fingers not operating well. Retro Bill Quote Link to comment Share on other sites More sharing options...
+acadiel Posted March 29, 2020 Share Posted March 29, 2020 I'm wondering how hard it would be in programmable logic for us to to emulate the CRU Bank switching nowadays. It's just a 64K SRAM chip with a PAL/GAL controlling bank switching via CRU. (I think this is how it works - someone please correct me if I'm wrong on any of these points.) We can probably take the 128K board or Ksarul's Supercart board and adapt the pinout of the 378 for the PAL/GAL, plus make space for an EA GROM. We'd have to get community involvement to develop the PAL/GAL formulas. All that happens (just off the top of my head) is that bit patterns are written to CRU >0800 (0001, 0010, 0100, and 0110 for the 32K one, more for the 64K one). These then enable/disable address lines on the 64K SRAM so you get different 8K space: 0000 0000 0000 0000 - 0001 1111 1111 1111 - 0-8191 >0000-1FFF 0010 0000 0000 0000 - 0011 1111 1111 1111 - 8192-16383 >2000-3FFF 0100 0000 0000 0000 - 0101 1111 1111 1111 - 16384-24575 >4000-5FFF 0110 0000 0000 0000 - 0111 1111 1111 1111 - 24576-32767 >6000-7FFF You could also continue the pattern for a 64K SRAM: 1000 0000 0000 0000 - 1001 1111 1111 1111 - 32767-40959 >8000-9FFF 1010 0000 0000 0000 - 1011 1111 1111 1111 - 40960-49151 >A000-BFFF 1100 0000 0000 0000 - 1101 1111 1111 1111 - 49152-57343 ->C000-DFFF 1110 0000 0000 0000 - 1111 1111 1111 1111 - 57344-65535 >E000->FFFF I don't think they designed this to be more extensible than 64K because of them using the first set of four bits to present to the CRU address. Were there other ways around this? Quote Link to comment Share on other sites More sharing options...
HOME AUTOMATION Posted March 29, 2020 Share Posted March 29, 2020 1 hour ago, acadiel said: I don't think they designed this to be more extensible than 64K because of them using the first set of four bits to present to the CRU address. What you talkin' 'bout ...Willis? Most, but not all of this, makes sense to me. I am only familiar with a 32k SUPERCART scheme. Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted March 29, 2020 Share Posted March 29, 2020 1 hour ago, HOME AUTOMATION said: I am only familiar with a 32k SUPERCART scheme. SuperSpace II is 32k CRU-switched banking. The manual includes information on how to accomplish the bank-switching. Quote Link to comment Share on other sites More sharing options...
+acadiel Posted March 29, 2020 Share Posted March 29, 2020 4 minutes ago, OLD CS1 said: SuperSpace II is 32k CRU-switched banking. The manual includes information on how to accomplish the bank-switching. DataBiotics used the SS scheme on a few carts: Red Baron (32K) Desktop Publisher (32K) TI Workshop (64K) Stargazer I/II/III (32K) So yeah, it’s definitely extensible to 64K. They probably just didn’t do it. 1 Quote Link to comment Share on other sites More sharing options...
HOME AUTOMATION Posted March 29, 2020 Share Posted March 29, 2020 Sorry @OLD CS1, I meant, SuperSpace II (32k). But... @acadiel, Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 29, 2020 Share Posted March 29, 2020 Superspace III went to 64K, but I've only ever seen one of those, and it was a prototype. 1 Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted March 29, 2020 Share Posted March 29, 2020 Just now, Ksarul said: Superspace III went to 64K, but I've only ever seen one of those, and it was a prototype. I wonder if the hardware in the SSII will support 64k... 1 Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 29, 2020 Share Posted March 29, 2020 ISTR that the PAL in it does support switching up to 64K, which makes sense, as TI workshop actively uses a 64K space, and it is based off of the SS II board. 1 Quote Link to comment Share on other sites More sharing options...
+adamantyr Posted March 29, 2020 Share Posted March 29, 2020 I have a Super Space II, with disk and manual. Got it on eBay a few years back when that cache of NOS stuff was found and put up. I'm not sure I want to part with it, but in truth I don't need it. I'm using SAMS now for most of my development which is superior for memory availability. You can PM me an offer if you want. 1 Quote Link to comment Share on other sites More sharing options...
+acadiel Posted March 29, 2020 Share Posted March 29, 2020 4 hours ago, Ksarul said: ISTR that the PAL in it does support switching up to 64K, which makes sense, as TI workshop actively uses a 64K space, and it is based off of the SS II board. Yep. Supposedly the fuses are burnt, so I can't read the ones in mine. But we pretty much know the logic and writes (which enable certain address lines in the ROM/RAM), so the community can definitely figure out the GAL/PAL. Quote Link to comment Share on other sites More sharing options...
+acadiel Posted March 29, 2020 Share Posted March 29, 2020 (edited) TI Workshop uses a PAL16R4A-2CN. 64K. 27512 EPROM. None of my programmers can read/write these. There likely needs to be an older model for this kind. PAL16R4A-2CN Pinout: 1 - N/C 2 - DBIN 3 - A12 4 - A11 5 - A10 6 - A3 7 - A8 8 - A1 9 - A0 10 - GND 11 - VCC 12 - N/C 13 - N/C 14 - N/C 15 - A13 16 - A14 17 - A15 18 - CRUCLK 19 - A4 20 - GND No idea why they hooked up all these address lines when they only really needed to control four of them. Plus, they left out A2, A5, A6, A7, and A9. Thoughts? Edited March 29, 2020 by acadiel 3 Quote Link to comment Share on other sites More sharing options...
+Torrax Posted March 30, 2020 Share Posted March 30, 2020 Wasn't Edgar L. Dohman (SuperBug II) involved in the development of the Super Space cartridge? He also had some h/w modification back in 1985/86 to support 128K in these carts. Barry Boone might know more as his SoundFX program also mentions support of up to 128K with the SuperSpace. Quote Link to comment Share on other sites More sharing options...
+Torrax Posted March 30, 2020 Share Posted March 30, 2020 Here's my Super Space II and the page with the jumpers from the manual. 3 Quote Link to comment Share on other sites More sharing options...
Tursi Posted March 30, 2020 Share Posted March 30, 2020 CRU is pretty straight forward, I don't think it would be hard to mock it up in VHDL. But since some consoles don't have the CRUOUT on the cartridge port, do we need to create new software that uses it? Quote Link to comment Share on other sites More sharing options...
HOME AUTOMATION Posted April 1, 2020 Share Posted April 1, 2020 On 3/29/2020 at 10:50 PM, Tursi said: But since some consoles don't have the CRUOUT on the cartridge port I see no, pin 6 CRUIN, in the TI-99/4QI schematics. Which TIs, have no CRUOUT from the GROM PORT? Quote Link to comment Share on other sites More sharing options...
Tursi Posted April 3, 2020 Share Posted April 3, 2020 On 3/31/2020 at 9:41 PM, HOME AUTOMATION said: I see no, pin 6 CRUIN, in the TI-99/4QI schematics. Which TIs, have no CRUOUT from the GROM PORT? My understanding was the QI machines lack it. Haven't personally tested that. 1 Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted April 3, 2020 Share Posted April 3, 2020 26 minutes ago, Tursi said: My understanding was the QI machines lack it. Haven't personally tested that. I have a QI for certain. I will see if I have cartridges known to use CRU bank switching, maybe fire up my SSII. Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted April 3, 2020 Share Posted April 3, 2020 Do "Super Space" and "Super Space III" also contain batteries ? Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted April 3, 2020 Share Posted April 3, 2020 38 minutes ago, Schmitzi said: Do "Super Space" and "Super Space III" also contain batteries ? Yes. 2350, IIRC. 1 Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted April 3, 2020 Share Posted April 3, 2020 (edited) 11 minutes ago, OLD CS1 said: Yes. 2350, IIRC. Why ? What is it needed for ? ah, this is NOT a game, this is a tool ? Edited April 3, 2020 by Schmitzi Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted April 3, 2020 Share Posted April 3, 2020 The battery maintains the 8k or 32k RAM. Correct, the SuperSpace is a tool, on par with the MiniMemory but with an E/A GROM included. 1 Quote Link to comment Share on other sites More sharing options...
FDOS Posted April 4, 2020 Author Share Posted April 4, 2020 On 3/29/2020 at 1:01 PM, adamantyr said: I have a Super Space II, with disk and manual. Got it on eBay a few years back when that cache of NOS stuff was found and put up. I'm not sure I want to part with it, but in truth I don't need it. I'm using SAMS now for most of my development which is superior for memory availability. You can PM me an offer if you want. I sent the PM. Let me know when you get it or not. I screw up a lot. Retro Bill Quote Link to comment Share on other sites More sharing options...
RXB Posted April 4, 2020 Share Posted April 4, 2020 (edited) I bought the Super Space 2 after already owned the Super Space 1. The huge issue is you have to have someplace to put the CRU access so the >6000 space is always devoted to CRU switching pages. Thus almost impossible to use for duplication of any ROM module. A much better idea would have been like the XB ROM switching method or writting to >7FFF for up to 256 banks of ROM/RAM. Many programs could then switch the page rather then being stuck with CRU programs being exactly at same spot on each page. Edited April 4, 2020 by RXB Quote Link to comment Share on other sites More sharing options...
FDOS Posted April 5, 2020 Author Share Posted April 5, 2020 10 hours ago, RXB said: I bought the Super Space 2 after already owned the Super Space 1. The huge issue is you have to have someplace to put the CRU access so the >6000 space is always devoted to CRU switching pages. Thus almost impossible to use for duplication of any ROM module. A much better idea would have been like the XB ROM switching method or writting to >7FFF for up to 256 banks of ROM/RAM. Many programs could then switch the page rather then being stuck with CRU programs being exactly at same spot on each page. The way in which I will be using it is not a problem, as I've already done it in MAME SNUG TI emulation. Initially, I was trying to use the 4 resident RAM/ROM banks in the first 8 HSGPL RLM for TI BASIC programs, and the second 8 for modules of my choice. The problem is the SNUG HSGPL CRU addressing is only the same as Super SPACE for the first bank; all the rest are different! Therefore, for non-SNUG TI purposes I choose to use the Super Space II module with my real TI-99/4A w/TI Speech and NanoPEB system. I guess I forgot to mention that I'm using BCART in the 4 banks for TI Basic Plus programs I create myself. The bank switching is done with CALLs to AL code in the 32K memory, along with a flag for an ON GOTO or ON GOSUB in each bank. I just have to say that Brad Snyder did a brilliant job with BCART. The more I use it and learn about it the more I like it over MSAVE, as RESTORE (line-number) works great, and it's so much FUN to use. Retro Bill 3 Quote Link to comment Share on other sites More sharing options...
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