Blinky Posted December 2, 2023 Share Posted December 2, 2023 17 minutes ago, Thomas Jentzsch said: What makes you think so? because it doesn't add up 26 minutes ago, Thomas Jentzsch said: The dumper will most likely return random values anyway I don't agree with the random values bit of hot spots but that' doens't matter the dumper transmits the dump that it read, creates some crc and transmits that in the end of rom dump part. Also dumping the same cart multiple times with or without power cycle returns the same dump and crc When I change that crc value of a dumped rom, it won't be accepted. The dump only gets accepted when it has the same value as when it was dumped. Quote Link to comment Share on other sites More sharing options...
Spanner Posted December 2, 2023 Share Posted December 2, 2023 (edited) 2 hours ago, NinjaWarrior said: Then why most games won't work on it I'm getting confused, is it buildroot or Stella? Anyhow, why doesn't the Genesis Controller don't work, But the SMS Controller does? The main Firmware it runs is Linux(Buildroot) and run inside it Stella the Emulator when it dumps a cart, Stella is not the firmware. Maybe the SMS controller works cause it dose not have a chip(IC) inside it, AFAIK the Mega Drive Control Pad does, because it has extra buttons B,C and Start, the Atari Joysticks do not have a chip in them too so it thinks the SMS Control Pad is a Atari joystick, I think Quick Joy Joysticks will work too, just make sure they have no chip in them like for turbo fire and that. One of the MCU is acting like a USB IC that would be in a joystick(like in THEC64 Joystick GH001 USB IC) if it had USB ports on the Atari2600+ the USB IC would be in the joystick so the joystick you use or try has to be compatible with it and have a direct connection to it to work so to the joysticks UP, Down, Left, Right and Fire in the MCU IC so it works the same way as THEC64 Joystick works so its USB IC on its board connects straight to Up, Down, Left, Right and Fire. It works the same as if you added a DB9 port on to THEC64 Joystick, thats what they have done on the Atari2600+ basically. Edited December 2, 2023 by Spanner Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted December 2, 2023 Share Posted December 2, 2023 (edited) 1 hour ago, Blinky said: because it doesn't add up Have you tried with different initial values? 1 hour ago, Blinky said: I don't agree with the random values bit of hot spots but that' doens't matter the dumper transmits the dump that it read, creates some crc and transmits that in the end of rom dump part. Also dumping the same cart multiple times with or without power cycle returns the same dump and crc Interesting. Are you testing bankswitched carts like F8? 1 hour ago, Blinky said: When I change that crc value of a dumped rom, it won't be accepted. The dump only gets accepted when it has the same value as when it was dumped. Hm, what could that be useful for? Is the cart maybe dumped twice? Edited December 2, 2023 by Thomas Jentzsch Quote Link to comment Share on other sites More sharing options...
Blinky Posted December 2, 2023 Share Posted December 2, 2023 9 minutes ago, Thomas Jentzsch said: Have you tried with different initial values? Yes, I've also included the 5 byte header but didn't find any similarities (yet). I've modded my 2600+ now so I can stream the dumped roms but I need to figure out the crc now so I can load other roms too 15 minutes ago, Thomas Jentzsch said: Are you testing bankswitched carts like F8? Yes tested a few. 18 minutes ago, Thomas Jentzsch said: what could that be useful for? integrity check. Just to make sure the dump is received correctly over the serial link. The dumper only sends the dump once after the dumper has done all it's magic internally. 1 Quote Link to comment Share on other sites More sharing options...
Spanner Posted December 3, 2023 Share Posted December 3, 2023 (edited) On 11/23/2023 at 9:10 PM, karri said: The easiest way might be to ask for it. But this may be difficult as the credentials are the same for all units. You do not want hackers to install their own stuff on machines. I would not share it. The chip has a mask rom booting capability. You can just write your own firmware from scratch and install it . Or wait until they have a good enough firmware that allows us to run homebrews on the 2600+. PLAION(Koch Media, Ben Jones) didn't mind the Capcom Home Arcade been hacked with CHOKO.. Its posted on there reddit(some of the stuff was add to its firmware too like a mode that turns the CHA into 2 PC Joysticks so you can use it with Mame or a game on the PC) I never new what a CHA was untill the hack came out, my friend worked on it and I will only be puting on it Atari stuff so no Retroarch, anyway it would not work, it does not enough ram, the Atari 800 Emulator would, we will see once I get in... Edited December 3, 2023 by Spanner Quote Link to comment Share on other sites More sharing options...
+karri Posted December 3, 2023 Share Posted December 3, 2023 The stock credentials for busybox are login: root, pw: <ENTER> 1 Quote Link to comment Share on other sites More sharing options...
Spanner Posted December 3, 2023 Share Posted December 3, 2023 2 minutes ago, karri said: The stock credentials for busybox are login: root, pw: <ENTER> `rk312x login:` I type `root` and then enter and then enter again and its says `Login incorrect` I am booting it normally and putty is connected to its UART. 1 Quote Link to comment Share on other sites More sharing options...
+karri Posted December 3, 2023 Share Posted December 3, 2023 As the checksum is just one byte I am happy with a script that tries 256 downloads. One of them will work 😁 Quote Link to comment Share on other sites More sharing options...
Blinky Posted December 3, 2023 Share Posted December 3, 2023 256 download attemts is a long time. Would be cool if we can crack it. sofar I got two 4k and 16K rom pairs that produce the same crc (but have totally different regular checksums) Figured out the last two bytes (rom type) are not included in the crc calculation and the rom seems to load fine if these two bytes have random values. Quote Link to comment Share on other sites More sharing options...
+karri Posted December 3, 2023 Share Posted December 3, 2023 I assume that you already tried xor, sum and crc-8. Atari Lynx used subtract for obfuscating the encrypted blocks. The carry was passed over all bytes. They started the subtraction from the last byte. Quote Link to comment Share on other sites More sharing options...
Blinky Posted December 3, 2023 Share Posted December 3, 2023 I just discovered you can swap bytes, nibbles and bits of a rom and it still loads fine (with the same working crc) so it is something to do with parity and/or bit counting. Quote Link to comment Share on other sites More sharing options...
+karri Posted December 3, 2023 Share Posted December 3, 2023 1 hour ago, Blinky said: I just discovered you can swap bytes, nibbles and bits of a rom and it still loads fine (with the same working crc) so it is something to do with parity and/or bit counting. Sounds so much like a XOR... Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted December 3, 2023 Share Posted December 3, 2023 (edited) 4 hours ago, karri said: Sounds so much like a XOR... But then swapping bits or nibbles should change the result. Maybe there is a parity bit calculated per page (256 bytes) or bank (4096 bytes). And these are then combined to form a checksum byte. Edited December 3, 2023 by Thomas Jentzsch 1 Quote Link to comment Share on other sites More sharing options...
Blinky Posted December 3, 2023 Share Posted December 3, 2023 5 hours ago, Thomas Jentzsch said: Maybe there is a parity bit calculated It's definitely parity related as the rom still passes when setting or clearing an even number of bits. 1 Quote Link to comment Share on other sites More sharing options...
+karri Posted December 3, 2023 Share Posted December 3, 2023 41 minutes ago, Blinky said: It's definitely parity related as the rom still passes when setting or clearing an even number of bits. So you could xor the bytes over the range and finally reduce the last byte to a bit to see if it is even or odd. Quote Link to comment Share on other sites More sharing options...
kelvinator3300 Posted December 10, 2023 Share Posted December 10, 2023 since this thing will play old carts (or am i wrong about that?) it seems like the crc would be documented somewhere already...from the original 40+ year old system/carts. there's no way someone never cracked that. 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted December 10, 2023 Share Posted December 10, 2023 3 hours ago, kelvinator3300 said: since this thing will play old carts (or am i wrong about that?) it seems like the crc would be documented somewhere already...from the original 40+ year old system/carts. there's no way someone never cracked that. The carts are not check-summing. 1 Quote Link to comment Share on other sites More sharing options...
+karri Posted December 10, 2023 Share Posted December 10, 2023 5 hours ago, kelvinator3300 said: since this thing will play old carts (or am i wrong about that?) it seems like the crc would be documented somewhere already...from the original 40+ year old system/carts. there's no way someone never cracked that. There was a hash for 7800 NTSC carts and an encryption with obfuscation for the Lynx carts. This was to prevent creation of unauthorized carts. These keys are known today. The check sum is just for checking that the transmission from the dumper to the CPU is correct. But there is dozens of ways to calculate it. We have an idea how it works but the small details are not known. Quote Link to comment Share on other sites More sharing options...
WhyLee commotari.club Posted December 11, 2023 Author Share Posted December 11, 2023 On 12/10/2023 at 10:57 AM, karri said: There was a hash for 7800 NTSC carts and an encryption with obfuscation for the Lynx carts. This was to prevent creation of unauthorized carts. These keys are known today. I guess this was also needed to distiguish if it is a 2600 or 7800 cartridge. Before starting a 2600 cartridge they had to shut down other hardware in the 7800 to stay compatible. Chip select logic for example. Quote Link to comment Share on other sites More sharing options...
+karri Posted December 11, 2023 Share Posted December 11, 2023 47 minutes ago, WhyLee commotari.club said: I guess this was also needed to distiguish if it is a 2600 or 7800 cartridge. Before starting a 2600 cartridge they had to shut down other hardware in the 7800 to stay compatible. Chip select logic for example. The PAL version of the 7800 does not have this. Perhaps there was some technical reason I am unaware about. The only reason I could see was to prevent unauthorized developers to access Maria. (the 7800 graphics chip) Quote Link to comment Share on other sites More sharing options...
Stechmann Posted March 21 Share Posted March 21 This thread seems to have died down. I am anxiously waiting for a way to sideload homebrew ROMs to the 2600+. Is there a way to do this? 2 Quote Link to comment Share on other sites More sharing options...
Spanner Posted March 21 Share Posted March 21 (edited) Yes... https://github.com/CommodoreOS/PCUAE You can run roms in it but have to have a cartridge in the slot(10 in1 cartridge) so it loads it and the switches work on the console, you can disable the DMenu too so just load Retroarch but the switches do not work then. #------------------------------------------------------------------------------------------------# ***Project Carousel USB Anniversary Edition(PCUAE) by Spannernick*** PCUAE idea and created by Spannernick, RetroNuts on YouTube, For THEC64 Mini,THEC64 Maxi,THEVIC 20, and now for THEA500 Mini and Atari 2600 plus too This is free for non commercial use, NOT to SELL. ***HELP*** #------------------------------------------------------------------------------------------------# # Press and HOLD DOWN CTRL Key then Press the other Key and HOLD both DOWN for 2 seconds # # or for as long as it takes for the screen to goes black(blank). # #=================================================================================================# CTRL+F1 - Enable Stella Mode, Run ROM Game Files in Stella. CTRL+F2 - Enable Stella Cartridge Mode, Run 2600 Cartridges in Stella Only, not 7800. CTRL+F3 - Retroarch Mode(beta), Run Retroarch GUI and its Cores. CTRL+F4 - Back to PCUAE Mode, back too or Restart PCUAE Mode. CTRL+F5 - Amiga Mode(PUAE) Amiga Workbench 1.3. CTRL+F6 - MSX/Colecovision Mode, Run ROM Games for MSX and COL. CTRL+F7 - ATARI ST Mode, Run the Atari ST Hard Drive CTRL+F8 - Vice Mode, Run 6 CBM Machine, VIC20, PET, C64, C16/Plus4, C128 and C64 DTV. CTRL+F9 - Power Off Safely(USB DRIVE). CTRL+F10 - Reset. #=================================================================================================# CTRL+? - Disable Atari2600 Plus Shortcut Key Selector, to use the shortcuts in Stella. You only need to do this if your running Stella and want to use one of its CTRL and F keys. Press CTRL+? again to enable this again to turn it on. #=================================================================================================# #=================================================================================================# Atari 2600/7800 Games On PCUAE USB Drive for the Atari2600 Plus #=================================================================================================# CTRL+1 - Enable Astroids... CTRL+2 - Enable Berzerk Voice... CTRL+3 - Enable BMX Airmaster... CTRL+4 - Enable Winter Games... CTRL+5 - Enable Baby Pac Man(7800)... CTRL+6 - Enable Choplifter... CTRL+7 - Enable Graze... CTRL+8 - Enable Super Stunt Cycle(7800)... CTRL+9 - Enable Pole Position II(7800)... CTRL+0 - Enable your own game... #=================================================================================================# #=================================================================================================# CTRL+E - Experiment Mode(EXF)(Experimental Firmware v1.1x-r2, version 2). Use at your own risk, might have bugs, by Raz0red, Ben and the PLAION Team, from Atari Age forum, Beta Firmware. #=================================================================================================# CTRL+R - Toggle 50/60Hz Mode, 50hz PAL or 60hz NTSC, 60hz is faster then 50hz so games will run faster if your on 50hz but if your on 60hz already then if changed to 50hz it will run the game slower. #=================================================================================================# CTRL+D - Toggle Dmenu Enble, Disable, Disabling the DMENU will disable the SELECT,RESET Switches On the console but can boot a game from USB without a cartridge in the slot. #=================================================================================================# Edited March 21 by Spanner 1 Quote Link to comment Share on other sites More sharing options...
shane857 Posted March 21 Share Posted March 21 Just...Why??? Why load roms on the Atari 2600+, When it was designed for physical carts? You can do this on a multitude of devices anyway... Quote Link to comment Share on other sites More sharing options...
HatNJ Posted March 21 Share Posted March 21 Same can be said for original 2600/7800 hardware as well. But we have multiple flash carts for those/ Quote Link to comment Share on other sites More sharing options...
shane857 Posted March 21 Share Posted March 21 8 minutes ago, HatNJ said: Same can be said for original 2600/7800 hardware as well. But we have multiple flash carts for those/ Fair point. I have no interest personally in loading roms off the 2600+ and the original VCS with flash carts, so I will not reply to this topic any further. Quote Link to comment Share on other sites More sharing options...
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