Gazoo Posted March 20, 2014 Share Posted March 20, 2014 Pictured is the Mechatronics XB cartridge. Is anyone here real familiar with it's construction? (I'm betting there's one person in particular that is). The question is: Are the 3 large chips (2 are stacked) on the left Proms with the Grom/Rom code? If they are, I'm interested in replacing them with a different version of XB. That process would seem pretty straightforward - desolder the chips, read them to find out the layout, and burn new eproms to replace them. The 8 soldered-in chips to the right all seem to be standard logic chips. The socketed chip in the middle appears to be a custom chip and would be the deal breaker if an attempt were made to duplicate the cart. Thoughts? Gazoo Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 20, 2014 Share Posted March 20, 2014 One of the chips is the ROM, and the stack is the simulated GROM. the 4 LS161s are the counters that simulate the GROM address auto-increment feature, the LS139 is doing the bank switching on the ROM. The other two chips are also part of the GROM selection circuitry. What you have is a 40K GROM and 32K ROM cartridge board. Since it is using the 379, it is using the inverted banking mode (unless they've done something on there to modify that, not likely). Quote Link to comment Share on other sites More sharing options...
CantStopClicking Posted March 20, 2014 Share Posted March 20, 2014 Mechatronic XB.jpg Pictured is the Mechatronics XB cartridge. Is anyone here real familiar with it's construction? (I'm betting there's one person in particular that is). The question is: Are the 3 large chips (2 are stacked) on the left Proms with the Grom/Rom code? If they are, I'm interested in replacing them with a different version of XB. That process would seem pretty straightforward - desolder the chips, read them to find out the layout, and burn new eproms to replace them. The 8 soldered-in chips to the right all seem to be standard logic chips. The socketed chip in the middle appears to be a custom chip and would be the deal breaker if an attempt were made to duplicate the cart. Thoughts? Gazoo Is the capacitor by the mounting hole bad? Looks almost like it's split from the picture. On a side note; Does anyone have a 'first step' for someone trying to figure out why their Mechatronics XB cartridge doesn't work? When I insert it in to the TI and turn it on, the screen changes color but immediately locks up. And not really sure how or where to start the trouble-shooting process (if there is one). TIA! -Dano Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 20, 2014 Author Share Posted March 20, 2014 (edited) One of the chips is the ROM, and the stack is the simulated GROM. the 4 LS161s are the counters that simulate the GROM address auto-increment feature, the LS139 is doing the bank switching on the ROM. The other two chips are also part of the GROM selection circuitry. What you have is a 40K GROM and 32K ROM cartridge board. Since it is using the 379, it is using the inverted banking mode (unless they've done something on there to modify that, not likely). Thank you sir. I knew it would be you who answered. Got any more info on the stacked Grom (simulated) chips? Are there eproms that match the pinouts? I don't need to change the Rom. So this is starting to look quite doable. Gazoo Edited March 21, 2014 by Gazoo 1 Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 20, 2014 Author Share Posted March 20, 2014 Is the capacitor by the mounting hole bad? Looks almost like it's split from the picture. On a side note; Does anyone have a 'first step' for someone trying to figure out why their Mechatronics XB cartridge doesn't work? When I insert it in to the TI and turn it on, the screen changes color but immediately locks up. And not really sure how or where to start the trouble-shooting process (if there is one). TIA! -Dano Didn't notice the bad cap, doesn't seem to affect performance. Thanks. Gazoo 1 Quote Link to comment Share on other sites More sharing options...
Gary from OPA Posted March 21, 2014 Share Posted March 21, 2014 oh,no destorying a meachatronic xb cart.... so sad, there is so little of them left. Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 21, 2014 Author Share Posted March 21, 2014 oh,no destorying a meachatronic xb cart.... so sad, there is so little of them left. Not destroying, turning it into an XB v2.7 cart. Big improvement. Gazoo Quote Link to comment Share on other sites More sharing options...
CantStopClicking Posted March 21, 2014 Share Posted March 21, 2014 Didn't notice the bad cap, doesn't seem to affect performance. Thanks. Gazoo That's a plus! Now, if I could just get mine to work... The chip in the socket I believe is a N82S123 (a 256-bit TTL bipolar PROM). Or so I'm assuming; from to the datasheet that I was able to dig up on that guy. I've attached it in case it's of some use. Best of luck! -Dano N82S123 (256-bit TTL bipolar PROM).pdf Quote Link to comment Share on other sites More sharing options...
+acadiel Posted March 21, 2014 Share Posted March 21, 2014 (edited) Are the 9128 chips simply 16Kx8 (i.e. equivalent of a 27128, or 16K apiece?) If there are three of those, then there's 48K combined of ROM and GROM code? i'm guessing the socketed chip with the green dot is a PAL? Edit: I saw that the N82 chip is this one: http://www.plccenter.com/buy/SIGNETICS/N82S23N - 32Kx8 - equivalent of a 27256, or 32K. I've never seen a ROM of that vintage in that DIP size. So, 48K GROM + 32K ROM? Edited March 21, 2014 by acadiel Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 21, 2014 Share Posted March 21, 2014 Actually, the N82S23 is a 32word x 8bit chip--not a 32K chip. I'm not sure what they're using it for here. They are using the other three ROMs as a 32K ROM, banked in 8K increments and likely a single 32K ROM with an 8K ROM to give 40K of GROM. 1 Quote Link to comment Share on other sites More sharing options...
CantStopClicking Posted March 21, 2014 Share Posted March 21, 2014 That's a plus! Now, if I could just get mine to work... The chip in the socket I believe is a N82S123 (a 256-bit TTL bipolar PROM). Or so I'm assuming; from to the datasheet that I was able to dig up on that guy. I've attached it in case it's of some use. Best of luck! -Dano Ooops, my bad on the N82S23N, which is not the same as the datasheet for the N82S123N I had previously thought was it. Soon as I think I know what I'm talking about, the world reminds me I don't have a f'ing clue... LOL -Dano Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 22, 2014 Author Share Posted March 22, 2014 oh,no destorying a meachatronic xb cart.... so sad, there is so little of them left. What ever became of the Pop Cart, Gary? Was there ever a working model, and any type of production of it? Maybe if I can get one, I won't have to 'destroy' my Mechatronic cart. Gazoo 1 Quote Link to comment Share on other sites More sharing options...
apersson850 Posted March 22, 2014 Share Posted March 22, 2014 As far as I can remember, I can run a copy of Mechatronic XB in my Maximem module. Quote Link to comment Share on other sites More sharing options...
Gary from OPA Posted March 22, 2014 Share Posted March 22, 2014 (edited) What ever became of the Pop Cart, Gary? Was there ever a working model, and any type of production of it? Maybe if I can get one, I won't have to 'destroy' my Mechatronic cart. Gazoo PoP-Cart. <-- Pile-of-Programs ---> Full design overrides Groms 0/1/2 with an new fully licensed OS from TI (produced by OPA) and includes a CART. device DSR (yes a DSR in module form, it even has a CRU base!), with full 8 banks times 8 slots of GROMs in one 512K eprom and another 128k eprom containing 2 banks times 8 slots of ROM, all accessabled via the 'review module library' design which been expanded on by new OS to make it easier, and allowed for some neat things, like the use of 'text-to-speech' from TE2 module while in XB if both were programmed to cartridge, and another neat tyhing the CART. device allow for actual files to store and ran like EA5 programs using a ROMdisk made up of all the empty space in module, since most cartridges are 6K per grom instead of 8K, so all that free space gets merged together by CART. device DSR into a nice accessable ROMdisk, and there was big program I made similar to 'module creator' that takes all your cartridges and files, and produces two images for you to burn the 512K grom eprom and 128k rom eprom. Yes wonderful design, been looking at seeing what I can recover and made available to the public. I have two fully working models with me here in DR, but sadly the original PCBoard artwork and PAL files have been lost, but one of these two models might have its chips not protected, I going to look at unsoldering and reading them on my programmer and see, the whole logic and grom simulator and bank switching was done in set of three PAL 22v10 chips, very neat and simple design. If not I have to regenerate the design from my head even tho my memory is great, would take more time. Sadly most time ended up destoried I think, the biggest shipment of completed units went to Asgard, for their XB+ contract, but sadly they never issued a payment, and the rest of unpopulated board were held at factory waiting for a while, and I tried to wrestle them out from my local business partner but he claimed he destoried them. Besides the two I have, not sure what happen to shipment to Asgard if they sold off the units, ship them to to fill existing preorders or just got stuck in warehouse someplace and forgotten about. Edited March 22, 2014 by Gary from OPA Quote Link to comment Share on other sites More sharing options...
Manic1975 Posted March 22, 2014 Share Posted March 22, 2014 I have one Mechatronic XB module. Sometime it lockup my TI99/4a when I use it few hours. Maybe console contact was resposible for this. Lockup happend only with Mechatronic XB module. Does anybody have spare Mechatronic XB silver sticker to send me? My is lost Quote Link to comment Share on other sites More sharing options...
humeur Posted March 22, 2014 Share Posted March 22, 2014 As far as I can remember, I can run a copy of Mechatronic XB in my Maximem module. Maximen 56 k no standard 48 k. Jean Louis Quote Link to comment Share on other sites More sharing options...
apersson850 Posted March 22, 2014 Share Posted March 22, 2014 Sounds likely. My Maximem is the 56 kbyte version. Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 27, 2014 Author Share Posted March 27, 2014 I was just looking a little closer at the cart. A photo of the bottom is included. Here's where it gets confusing. There is a solder bridge for pins 27 & 28 on the stacked chips. Pin 27 is the program voltage pin for 27c64 & 27c128 eproms, and it's A14 for 27c256 & 27c512 eproms. The 27c256 & 27c512 eproms will have their memory capacity cut in half by this solder bridge. Pin 20 is chip select for all of them, which makes sense, because that's the one pin of the stacked chips that's connected separately. I'm thinking of unsoldering these 2 chips this weekend so they can be dumped to find out the layout, but hesitation is creeping in because it doesn't seem that they will be able to be replaced directly with eproms. Whattayathink? Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted March 27, 2014 Share Posted March 27, 2014 Well, I tend to not want to be cavalier with someone else's property. That said, I assume you can remove the chips to try to read them, at least. You may uncover more information in the process. Provided that reading and your removal process are not destructive, you can reassemble with no problem. Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 28, 2014 Author Share Posted March 28, 2014 Well, I tend to not want to be cavalier with someone else's property. That said, I assume you can remove the chips to try to read them, at least. You may uncover more information in the process. Provided that reading and your removal process are not destructive, you can reassemble with no problem. Well, the removal and reassembling process should be non-destructive. I'm trying to get a few viewpoints on what the chips actually are based on the info we surmise so that the reading process will be non-destructive. Gazoo Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 29, 2014 Author Share Posted March 29, 2014 So far I've removed the top chip of the stacked ones. The chip below is revealed to be a 27128. I assume the top chip was compatible with a 27128 also because all pins were soldered to the chip below with the exception of the chip select pin and I've lost 16k of what was in the cartridge. I set up a Horizon to autoload a memory editor so I can see what's still in the cart. Groms 3, 4, & 5 are still there (g>6000 to g>BFFF). Groms 6 & 7 are no longer present (g>C000 to g>FFFF). Both Roms at c>6000 are still there. So if the other chip that's marked 9128C-1113 is also 16k, half of it must contain the last Grom, which leaves 8k. 8k is not enough for both Rom banks, we need at least 12k if they are just paging the 4k from c>7000 to c>7FFF or we need 16k if the whole 8k is being paged. Any ideas? Gazoo Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 29, 2014 Share Posted March 29, 2014 The one you removed is probably a 32Kx8, not a 16Kx8 like the one it was stacked on. Was your cart the Mechatronics XB or the XB2+? If it was the latter, you need additional space to store the APESoft routines--and they are only important from an access standpoint until they get loaded into low memory. Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 29, 2014 Author Share Posted March 29, 2014 (edited) The one you removed is probably a 32Kx8, not a 16Kx8 like the one it was stacked on. Was your cart the Mechatronics XB or the XB2+? If it was the latter, you need additional space to store the APESoft routines--and they are only important from an access standpoint until they get loaded into low memory. The cart includes the APESOFT routines. I'm not following your logic here. The APESOFT routines are stored in Grom 7 and moved to CPU memory by the command CALL APESOFT. Losing Groms 6 & 7 includes the area the APESOFT commands are stored. No additional memory other than g>6000 to g>FFFF and and the two 8k Rom banks are required to run this version of Mechatronic XB as I've run it from the Pgram card in the past. And the APESOFT commands worked fine. So there's still an apparent memory shortage. My guess at this point is that only 6k is used for the remaining 3 Groms is used as there is no code in the upper 2k of each. And the Rom is only banked switched for the top 4k. That would account for 30k of the 32k left. But it would make for some interesting splitting up of the 2 remaining memory chips. Gazoo Edited March 29, 2014 by Gazoo Quote Link to comment Share on other sites More sharing options...
Gary from OPA Posted March 29, 2014 Share Posted March 29, 2014 So there's still an apparent memory shortage. My guess at this point is that only 6k is used for the remaining 3 Groms is used as there is no code in the upper 2k of each. And the Rom is only banked switched for the top 4k. That would account for 30k of the 32k left. But it would make for some interesting splitting up of the 2 remaining memory chips. Gazoo Yep, the splitting logic for memory is messy, as such that is what the N82S32 (???) if my memory is serves me right still. It maps the logical memory address pins from grom simulator and rom banks into the actual physical memory position in the two programmed proms. Quote Link to comment Share on other sites More sharing options...
Gazoo Posted March 29, 2014 Author Share Posted March 29, 2014 Yep, the splitting logic for memory is messy, as such that is what the N82S32 (???) if my memory is serves me right still. It maps the logical memory address pins from grom simulator and rom banks into the actual physical memory position in the two programmed proms. Yes, so there's not going to be enough space to fit XB v2.7. Time to give up and put 'er back together. Gazoo Quote Link to comment Share on other sites More sharing options...
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