dirty-harry Posted January 16, 2015 Share Posted January 16, 2015 Has anyone done or thought of doing a Kickstart project to raise Money (seriously) to make a NEW TI-99/4A .. possibly out of sourced working TMS99xx ICs. Just updating the original design to take advanced of more modern SRAMs and V9938/58 VDP etc, yet still being software compatible. Ideally making it for less than $100 ! The design would be made Open-Source. Quote Link to comment Share on other sites More sharing options...
Stuart Posted January 16, 2015 Share Posted January 16, 2015 The point of view sometimes put forward is - if you update it like that, will it still be a TI-99/4A? What would be the market for a TI-99/4A that you've condensed down to just half a dozen chips? 'Real' systems are readily available, relatively cheap and reliable. There won't be much software support for new features unless you can achieve some sort of critical mass of users using it. All IMHO. Quote Link to comment Share on other sites More sharing options...
dirty-harry Posted January 16, 2015 Author Share Posted January 16, 2015 The idea is more to make a 'Kit' something like the original Powertran Cortex.. The Design would be open-source .. you'd buy say the PCB and source the ICs , resistors etc yourself or even buy a kit of parts ? Then You'd build and test it yourself. In the Same way the GR8BIT is to MSX (but simpler and much cheaper). It's not about building a computer.. you can get a second hand PC from ebay for peanuts ! It's about building and learning about microcomputers . Most Modern stuff is either surface mount or Microcontrollers ! And lots of modern stuff is way to FAST to breadboard as the wires act like radio-transmitters..making it more of an RF project ! Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted January 16, 2015 Share Posted January 16, 2015 I would be more apt to give to a Kickstarter project supporting the Geneve II. Quote Link to comment Share on other sites More sharing options...
Stuart Posted January 16, 2015 Share Posted January 16, 2015 I would be more apt to give to a Kickstarter project supporting the Geneve II. Not really sure though that Kickstarter is appropriate. There's little/no money in producing this stuff so they tend to be a labour of love in people's spare time. Would throwing Kickstarter money at it make it happen any quicker? Quote Link to comment Share on other sites More sharing options...
Stuart Posted January 16, 2015 Share Posted January 16, 2015 (edited) The idea is more to make a 'Kit' something like the original Powertran Cortex.. The Design would be open-source .. you'd buy say the PCB and source the ICs , resistors etc yourself or even buy a kit of parts ? Then You'd build and test it yourself. In the Same way the GR8BIT is to MSX (but simpler and much cheaper). It's not about building a computer.. you can get a second hand PC from ebay for peanuts ! It's about building and learning about microcomputers . Most Modern stuff is either surface mount or Microcontrollers ! And lots of modern stuff is way to FAST to breadboard as the wires act like radio-transmitters..making it more of an RF project ! I'm all for helping people play with hardware. Depending on how dirty you want to get your hands, there are some options available already: -- I've got breadboard designs for a basic TMS9995 (as used in the Cortex) and TMS99xxx systems on my website (www.stuartconner.me.uk), with BASIC and Forth available on EPROM. -- A couple of people have done further development on the 9995 breadboard design. There's now a version with a CF interface for storage and running barebones Unix. Bank switched RAM is going to be added to that, and I suspect it will be committed to a PCB as well. There's a chap in Australia who's done a PCB for the original barebones system, and that is probably going to be expanded as well. -- I know there's at least one other 'experimenters' 9995 design out there, but you would have to re-layout the PCB from photos. The F18A development lets you easily add a VDP with a VGA output - great as you don't have to touch any of that nasty analogue stuff! There's a chap on eBay who sells chip sets for 9900/9995 systems - but not for any particular design. Be aware that getting TMSxxxx chips off eBay at the moment can be a problem - there are lots of fakes from China, and a beginner trying to debug a system with a dodgy chip can be easily put off. My designs have been around for a while and I doubt that more than perhaps 6 people have used them. Edited January 16, 2015 by Stuart Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted January 17, 2015 Share Posted January 17, 2015 Not really sure though that Kickstarter is appropriate. There's little/no money in producing this stuff so they tend to be a labour of love in people's spare time. Would throwing Kickstarter money at it make it happen any quicker? Maybe a GoFundMe, instead, then. Quote Link to comment Share on other sites More sharing options...
PeBo Posted January 17, 2015 Share Posted January 17, 2015 (edited) Don't see a market for it... I can't speak for everyone, but the fun of my TI hobby are the very quirks of this machine that remodelling it would correct. I think items like Lothrek's HxC, the nanoPEB and the ubuiquitous F18A (not to mention the brilliant software and carts released over the past few years) is the real way to keep the TI alive among those of us who met her when she was still young and sexy. And while I'd jump at the chance to own a 99/8 (when I win a lottery), the stock 4A is what I loved when I was 25, and remains the computer I love as I'm pushing 60. And as other old farts like me will likely attest to, you just can't improve upon your first love! Edited January 17, 2015 by PeBo Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted January 17, 2015 Share Posted January 17, 2015 I think items like Lothrek's HxC, the nanoPEB and the ubuiquitous F18A (not to mention the brilliant software and carts released over the past few years) is the real way to keep the TI alive among those of us who met her when she was still young and sexy. I tend to think like you on this. "Back in the day", we were all upgrading our TI's with newer disk drives, controller cards, internal speech, clocks, printer buffers, RAM disks, Super Carts, mice, keyboard mods.... hey, WAIT A MINUTE... NOTHING HAS CHANGED! Quote Link to comment Share on other sites More sharing options...
Imperious Posted January 17, 2015 Share Posted January 17, 2015 (edited) Be aware that getting TMSxxxx chips off eBay at the moment can be a problem - there are lots of fakes from China, and a beginner trying to debug a system with a dodgy chip can be easily put off. I think You will find that the reputation for china producing fake chips has been blown out of proportion. I have bought many genuine "None left in the world" parts from china, and apart from 2 fake SID's, which I got a refund from, all others have been the genuine article. These are likely good too.. http://www.aliexpress.com/item/10PCS-free-shipping-100-new-original-TMS9900NL-TMS9900-original-spot/1777587556.html Chips I have purchased are TMS9929ANL, TMS9928ANL, 8362r2 Ted chips for a Commodore Plus/4, 6510 and 6526A c64 chips, 6561-101 Vic-20 Video/sound Ic's (these were supposed to be all gone), 16mhz 68000 chips for my Amiga, and lastly 8501r1 CPU's for a Commodore Plus/4 (still being shipped). I have bought other more generic parts like 6522's, 6502's, and various memory chips. Where I had any dead parts, like the 8362's I had good replacements sent. Considering that the Plus/4 chips are notorious for being the worst chips MOS Technologies ever made, it wasn't surprising that I got some DOA, but the sellers were reputable so no lost money. Edited January 17, 2015 by Imperious Quote Link to comment Share on other sites More sharing options...
simon ti99 Posted January 17, 2015 Share Posted January 17, 2015 As an educational tool for students and hobbyists to learn about microcomputer design and architecture I think it's a splendid idea but : Have you done any serious costing and what is the specification to be ?? How long would it take to design and test a prototype ? There's quite a lot of planning and project management involved to get a Working System to market! The ICs still look plentiful on ebay.com but you'd have to test them to route any defective or counterfeit chips.. Would it be an individual effort or a team project ? There's quite a lot to think about ! Quote Link to comment Share on other sites More sharing options...
dirty-harry Posted January 17, 2015 Author Share Posted January 17, 2015 Initial design would be based on costing and component availability Draft Specification would be : TMS9900 CPU PDIP64 TIM9904A PDIP TMS9901 PDIP Parallel I/O TMS9902 PDIP SIO Serail I/O 62256 SRAMs ( x 2) 16K bytes SRAM M27C128 UV EPROM (x 2) 32K bytes ROM Paged/banked ROM or NVRAM yet to be decided (512k Bytes?) TTL glue logic OR a CPLD to reduce cost V9958 Video VDP with 192K DRAM SN76489 Sound Chip AY-3-8910 or YM2149 Sound Chip with parallel ports 8255 PIO for IDE / CF Card PS/2 Keyboard interface Atari Joystick interface x 2 Real Time Clock RTC Maths Co-processor ?? Yet to be decidied Expansion connector for Daughter board to be fitted TIM9904 clock with 16MHz Crystal (overclocked) giving 4MHz Bus ! Spec for Daughter Board (optional): FDC Floppy Disk Controller Speech Chip Second IDE interface for IDE Hard-Drive Ethernet Note it's not intended to be a direct replacement for the original Ti-99/4A as the original computer had some weird idiosyncrasies. Only partial backward compatability would be achievable. Memory mapped I/O etc (were possible) would match tto he Ti-99/4A. IC costing : ( Main / Motherboard ) TMS9900 CPU PDIP64 $2 each TIM9904A PDIP $2.0 each TMS9901 PDIP Parallel I/O $2.0 each TMS9902 PDIP SIO Serail I/O $2.0 each 62256 SRAMs ( x 2) 16K bytes SRAM <$1.0 each M27C128 UV EPROM (x 2) 32K bytes ROM <$1.0 each Paged/banked ROM or NVRAM yet to be decided (512k Bytes?) TTL glue logic OR a CPLD to reduce cost CPLD (EPM7128) $2.0 each V9958 Video VDP with 192K DRAM $8.0 (for V9958+DRAMs) SN76489 Sound Chip <$0.75 each AY-3-8910 or YM2149 Sound Chip with parallel ports <$2.50 each 8255 PIO for IDE / CF Card <$2.0 each PS/2 Keyboard interface (small cheap MCU <$1.0 each) Real Time Clock RTC $2.5 each Maths Co-processor ?? Yet to be decidied $2.50 each I'd could get all the ICs for about $32 With a PCB , connectors, resistors etc I'd try to make it for $60. Some parts of the circuit have already been designed.. there's a working V9958 board on the web as a template for the video circuit as well as lots of other bits and pieces which could be modified as desired (with owner's permission). Costing Daughter Board (optional): FDC Floppy Disk Controller $2.50 each Speech Chip $3.50 each Second IDE interface for IDE Hard-Drive $2.50 each Ethernet $2.50 each PCB $25 Total cost approx $38 Timescale would be about six month to get a working prototype up and running. Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted January 17, 2015 Share Posted January 17, 2015 Caveat emptor - I have had a bunch of "TI" chips from China either counterfeit ot DOA. I order now from mainly US shippers on eBay or those from China that have a 99.7+% satisfaction rating. A lot of the chips from there are as bad as their English (Chinglish) instructions. Quote Link to comment Share on other sites More sharing options...
+save2600 Posted January 17, 2015 Share Posted January 17, 2015 Could a new TI have a real coffee warmer this time? The one in mine hardly works at all, specially during these sub zero temps. Quote Link to comment Share on other sites More sharing options...
bad robot Posted January 27, 2015 Share Posted January 27, 2015 Go for it ... You've got nothing to loose by giving it go ! Quote Link to comment Share on other sites More sharing options...
briantw Posted January 27, 2015 Share Posted January 27, 2015 Because those chips are no longer manufactured, is there any thought around creating whole new chips that are compatible with the old? Kind of like was done with the F18A. That way, you might find that you can replicate a whole bunch of ICs on a modern, programmable chip, saving a ton of space on your new, improved motherboard. Once you're using just a quarter, or less, of the motherboard real estate, you have a lot more space for upgrades, such as a NanoPEB equivalent, etc. Not that I could expect a small kickstarter to produce the level of large-scale integration that you might get from a Chinese chip plant, but just as an example of the miniaturisation possible, I have one of those Commodore 64-in-a-joystick thingies. 1 Quote Link to comment Share on other sites More sharing options...
Megatron1999 Posted January 27, 2015 Share Posted January 27, 2015 I believe someone has implemented a TMS9995 in VHDL.. but can't remember who ?? It would be a good idea to produce a modern better version of the TMS9900 series CPU with more addressable memory, Much Faster, more op-code efficient etc ... Though the cost and effort would be high ! If anyone has details about TMS99xx chips in VHDL please leave a message... Maybe one day there will be a 'One-Chip' TMS9900 system ? Quote Link to comment Share on other sites More sharing options...
briantw Posted January 27, 2015 Share Posted January 27, 2015 Maybe one day there will be a 'One-Chip' TMS9900 system ? I didn't want to be that optimistic, but hell yeah! Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted January 27, 2015 Share Posted January 27, 2015 There are at least two VHDL cores out there for the TMS9995. One was a commercial product with significant licensing costs and the other was developed for the Geneve II (which is still in slow, but active development the last I heard). Willsy, any new news there from your contacts? Quote Link to comment Share on other sites More sharing options...
killbot2000 Posted January 27, 2015 Share Posted January 27, 2015 Several months ago I was discussing the possibility of producing a TMS9900 system, in VHDL, with a small business in the US. They said they had TMS99xx cores in VHDL and a TMS9995 core and could do bespoke designs..obviously for money. Never got to the stage of getting a quote. But it does prove that it is possible to make/build a TMS99xx on a chip.. the tools and equipment are out there ! I've lost their email address !... and can't remember the name ! I suppose you could try Googling TMS9995 VHDL ?? Quote Link to comment Share on other sites More sharing options...
Willsy Posted January 27, 2015 Share Posted January 27, 2015 Gary Smith has a 9995 core in VHDL. It's not fully tested. I'll see if I can get the files. Quote Link to comment Share on other sites More sharing options...
killbot2000 Posted January 27, 2015 Share Posted January 27, 2015 To produce a 'One-Chip' TMS9900 system or System-On-a Chip , you'd need to prototype your code on a FPGA board something like an Altera DE0 or similar combining all the separate VHDL code into a working and tested system. This would take some time, but if a reasonable amount of the code is already written then it shouldn’t be too difficult. As a lot of code is already out there .. video (TMS9918,V9938??) sound Chips, CPUs , TMS9995? keyboard decoders, memory mappers etc then a lot of the work has already been done reducing the timescale considerably ! Quote Link to comment Share on other sites More sharing options...
mnbvcxz Posted January 27, 2015 Share Posted January 27, 2015 (edited) If you are thinking of creating a PCB and getting the user to acquire all the other components then how about a replacement PCB for the 99/4A. The new PCB would have 64KB CPU ram and dual clock speed and the F18A, maybe a CF card as well. Many of the components can be removed from the old board. If you need to make some room you could leave out the BASIC groms. Edited January 27, 2015 by mnbvcxz 1 Quote Link to comment Share on other sites More sharing options...
Micro-Designer Posted January 28, 2015 Share Posted January 28, 2015 Hi. About a year ago I had to cost a Very similar project (Single Board Computer SBC ) to this based on legacy ICs for a client. It didn't use a TMS9900/TMS9995 CPU, the costing where for a professional company to design and build from a 'Design Template' a Z80 SBC with video , sound and I/O etc. Three companies give free quotes which ranged from $10,000 to $15,000 to design/Build and functional test several prototypes. The price didn't include writing any software, OS etc. So for a 'Kick Start' project , to work you would probably need to raise $15,000 !! Hope this is useful ? Quote Link to comment Share on other sites More sharing options...
bad robot Posted January 28, 2015 Share Posted January 28, 2015 Hi. About a year ago I had to cost a Very similar project (Single Board Computer SBC ) to this based on legacy ICs for a client. It didn't use a TMS9900/TMS9995 CPU, the costing where for a professional company to design and build from a 'Design Template' a Z80 SBC with video , sound and I/O etc. Three companies give free quotes which ranged from $10,000 to $15,000 to design/Build and functional test several prototypes. The price didn't include writing any software, OS etc. So for a 'Kick Start' project , to work you would probably need to raise $15,000 !! Hope this is useful ? I'll pay ........ when I win the Lottery !! LoL ** Though jokes aside .. I still know companies that do TMS9995 type stuff !! Quote Link to comment Share on other sites More sharing options...
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