Tempest Posted January 3, 2015 Share Posted January 3, 2015 Did anyone see this? http://www.2600connection.com/interviews/todd_marshall/interview_todd_marshall.html At the bottom there's a link to some Frogger roms. Are any of these different than the final version? Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted January 3, 2015 Author Share Posted January 3, 2015 I was working on those ROMs a few months back (before the article made it online). There are about half a dozen bytes that change between these and the final ROMs--and they were just bug fixes. If I'd been given the source code listings at the same time I was asked to analyze the ROMs, this would have been even easier to determine. BTW, for those reading this--the source code to the Frogger cartridge is up there (non-editable PDF), for both the proto and the final code. The link to the music file is a dead link though. . . Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 3, 2015 Share Posted January 3, 2015 Any interesting bugs? Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted January 3, 2015 Author Share Posted January 3, 2015 I haven't taken time to analyze what each of the three bugs in the code did to it yet--my knowledge of Assembler isn't good enough to see their effects right off--I have to stumble through and come to a slow realization of what went wrong. . .and how. Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 3, 2015 Share Posted January 3, 2015 Oh, dont worry then. I might be misremembering this, but did someone say they had a version of Fantasy that could load from a EA cart? Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted January 3, 2015 Share Posted January 3, 2015 Good read. My favorite part from the Frogger development notes: I won't be here on Friday, so if you have any questions, tuff. Actually, interesting to see how software companies felt about and dealt with TI's GROM. Also sheds light on why the Parker Brothers games do not show the game name in the selection menu. 1 Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 5, 2015 Share Posted January 5, 2015 Also sheds light on why the Parker Brothers games do not show the game name in the selection menu. Why is that? Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted January 5, 2015 Author Share Posted January 5, 2015 The GROM code equivalent is a generic program that they put into all of their games so that they only had to write that portion of the code once. It gives the lead-in variables (number of players, difficulty) and passes control to the program--but it doesn't put the game's name on the title screen--it puts PARKER BROTHER'S GAME for all of them. Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 5, 2015 Share Posted January 5, 2015 Ah that makes sense. Quote Link to comment Share on other sites More sharing options...
Tursi Posted January 5, 2015 Share Posted January 5, 2015 That was an interesting article.. I've never had any of the Parker Brothers games -- was this a custom IC, then, or a discrete circuit? Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted January 6, 2015 Author Share Posted January 6, 2015 I think it was a custom IC, based on what I read in the rest of the system documentation--it was their way to get an auto-incrementing GROM equivalent without violating the TI patent. . . Quote Link to comment Share on other sites More sharing options...
Tursi Posted January 6, 2015 Share Posted January 6, 2015 That's what they /said/, but I have to wonder whether they did (infringe) or not. Obviously TI didn't care in the end. Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted January 6, 2015 Share Posted January 6, 2015 So, no one has pictures of the inside of one of these? Another thing I noticed was the mention of the 99/4A's sound list player and how sound lists contain a lot of redundant data. But not only can you make a good list without redundant data*, but SLR does not find a sound list in the PCROM or ROM files. They also mention that sound and graphics can be frozen a lot earlier than code (as I infer, anyway,) which I can see very clearly working on my own game. * Although, the concept of instruments would help quite a bit. Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted January 10, 2015 Author Share Posted January 10, 2015 This is also a mostly hardware thread, Albert. . . Quote Link to comment Share on other sites More sharing options...
Imperious Posted February 8, 2015 Share Posted February 8, 2015 (edited) I have a bunch of the 64k Jon Guidry boards, no components fitted yet, and am wondering if it is possible to modify them into a 512k board with a LS378 instead of the 379. I can't find schematics of the 512k board, but could figure it out myself if they are available. Maybe you already know all of this; but, for one thing, the 64KB board uses the 379 (quad latch) with its inverted outputs and a 378 (hex latch) does not have inverted outputs—so the boards are wired differently in that regard. A 378 has the same number of pins, but not one of the latch I/O pins are in the same place. Furthermore, the larger capacity EPROMs have 32 pins vs. the 28 of the 64KB (and lower) chips. You'll be doing quite a lot of surgery on a 64KB board to convert it to 512KB capacity, I should think. ...lee I've spent a few hours over the weekend armed with my multimeter, a bunch of PDF files on the computer screen, and both the UberGrom cart and the 64 Guidry boards. I am very confident that modifying the 64k boards into a 512k board with a 378 won't be as messy as I was originally thinking. There will still be fair bit of wrapping wire involved, but once tested and working will be inside a cart case and out of sight. I've ordered a bunch (10) AM25LS07's and 10 27c040's from Aliexpress, so in about a month should be able to post pics of a working example (I hope). The 27c040 is wired the same as the 27c512 from the bottom up. Only Pins 1, 2, 32, 31, 30 of the 040 will need special treatment, and I can Leave pins 1,8,9,16 of the 378 soldered to the 379 socket, the rest will involve wrapping wire and bent out pins. Edited February 8, 2015 by Imperious Quote Link to comment Share on other sites More sharing options...
Gazoo Posted February 8, 2015 Share Posted February 8, 2015 I've spent a few hours over the weekend armed with my multimeter, a bunch of PDF files on the computer screen, and both the UberGrom cart and the 64 Guidry boards. I am very confident that modifying the 64k boards into a 512k board with a 378 won't be as messy as I was originally thinking. There will still be fair bit of wrapping wire involved, but once tested and working will be inside a cart case and out of sight. I've ordered a bunch (10) AM25LS07's and 10 27c040's from Aliexpress, so in about a month should be able to post pics of a working example (I hope). The 27c040 is wired the same as the 27c512 from the bottom up. Only Pins 1, 2, 32, 31, 30 of the 040 will need special treatment, and I can Leave pins 1,8,9,16 of the 378 soldered to the 379 socket, the rest will involve wrapping wire and bent out pins. You may want to put a socket-in-a-socket to do the 378 mod. Not all of them power up in the first or last bank, so you may need a couple of tries to find one that does. Gazoo Quote Link to comment Share on other sites More sharing options...
Imperious Posted February 8, 2015 Share Posted February 8, 2015 Thanks for that idea, that will save me a lot of time and no wrecked chips in the process. Quote Link to comment Share on other sites More sharing options...
+acadiel Posted February 9, 2015 Share Posted February 9, 2015 Thanks for that idea, that will save me a lot of time and no wrecked chips in the process. Yep, and as the person that designed this board, trust me... there's tons of ways you can get to certain pins. What you are doing can be doable... but will take time, patience, and a lot of connections. :-) :-) I hacked my 64K board to do 128K, and also hacked it as a 128Kx4 board as well. Never tried changing out the 74LS379 to a 74LS378, but like Gazoo said... a socket on a socket (and changing the pins around accordingly) might be your best bet. Not quite as large as this pic, but it can be done. Quote Link to comment Share on other sites More sharing options...
Tempest Posted February 9, 2015 Share Posted February 9, 2015 I've been out of the loop for a bit on this. Have we discovered any other games on the 512K carts that don't work and have the ones that are broken been fixed yet? Any more carts being considered (Games 6)? Quote Link to comment Share on other sites More sharing options...
Imperious Posted March 26, 2015 Share Posted March 26, 2015 (edited) I finally got all the parts and modded one of my 64KB Jon Guidry boards into a 512KB board, and the good news is that it worked 1st time. Occasionally I have to turn off the computer and the NanoPEB as about 1/4 of the time I get a blank screen, works ok upon a proper reset usually. Only game that seems to not work is Car wars. Pins 1,2,8,9,16 of the 74ls378 (AM25LS07) are the same as the 379, all the rest as can be seen had to be changed. Pics attached, sorry for the slight out of focus images. The contacts aren't as dirty as the photos show, but I will clean them anyway. Only 5 more boards to go! Edited March 26, 2015 by Imperious 4 Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 26, 2015 Author Share Posted March 26, 2015 A relatively clean mod! Nice going Quote Link to comment Share on other sites More sharing options...
Astharot Posted March 27, 2015 Share Posted March 27, 2015 Imperius can write pin to pin your modding? in fact by photo i no look well.. sorry.. Quote Link to comment Share on other sites More sharing options...
+acadiel Posted March 27, 2015 Share Posted March 27, 2015 I finally got all the parts and modded one of my 64KB Jon Guidry boards into a 512KB board, and the good news is that it worked 1st time. Occasionally I have to turn off the computer and the NanoPEB as about 1/4 of the time I get a blank screen, works ok upon a proper reset usually. Only game that seems to not work is Car wars. Pins 1,2,8,9,16 of the 74ls378 (AM25LS07) are the same as the 379, all the rest as can be seen had to be changed. Pics attached, sorry for the slight out of focus images. The contacts aren't as dirty as the photos show, but I will clean them anyway. Only 5 more boards to go! That, my friend, is impressive and neatly done! Quote Link to comment Share on other sites More sharing options...
Imperious Posted March 29, 2015 Share Posted March 29, 2015 (edited) Imperius can write pin to pin your modding? in fact by photo i no look well.. sorry.. Hi. I have quickly scribbled a pinout for converting a 64k Jon Guidry board (27c512 and 74ls379) to a 512k board (27c040 and 74ls378(AM25ls07 same)) I am not interested in giving a step by step procedure at the moment as there are a few different ways You could achieve the same result, as in I chose to not cut tracks on the pcb, but that is a way if You prefer. PDF's of datasheets are easily findable for all the chips used and also the TI99/4a cartridge port pinout. However You mod the board it is a good idea to be able to swap the 74ls378 as some do not start in the correct bank, and You can't do that easily if it's soldered in. I would strongly suggest using a multimeter to figure out what goes where before modding, as some pins need to be changed and some do not. As an example Pins 1,2,8,9,16 of the LS378 are the same for the LS379, but pin 28 of the 27c512 is VCC whereas that becomes A17 on the 27c040 (pin 30) Edited March 29, 2015 by Imperious Quote Link to comment Share on other sites More sharing options...
Imperious Posted March 29, 2015 Share Posted March 29, 2015 Thanks for the nice comments everyone. I sorted the intermittent blank screen issues I was having with resetting the cart with a FCTN-QUIT and Car wars not working. I reseated the CF card in the nanoPEB and it all worked perfectly every time after that. I think also that I should be able to do a slight improvement to the modding next time as it appears I don't need to bend as many pins on the ls378 socket up as there are a few from the 379 pinout that don't go anywhere. Quote Link to comment Share on other sites More sharing options...
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