+wavemotion Posted November 5, 2022 Share Posted November 5, 2022 (edited) On 10/18/2022 at 10:35 AM, Eagle said: BTW DragonFly "Extended" version only plays Pokey music on DF with new firmware. Uses second 16KB RAM (hotspot at $FFFF) Question you might be able to answer, @Eagle Was there a reason the DragonFly used $FFFF as the hotspot vs the normal RAM banking (bit 5 of the banking write)? Was this to allow 1024K ROM games with 2x RAM? Anyway, I've now implemented the DF way of doing it. Is there any way from the .a78 header to know this is a 2x RAM game that uses the DF hotspot? The game is stunning! @playsoft in case you wanted to see it running under DS emulation: PS: I just realized there is a standard RAM bankswitching build further down the thread... oh well... at least now there are 2 things that support the DF way of doing it Edited November 5, 2022 by llabnip 3 1 Quote Link to comment Share on other sites More sharing options...
Eagle Posted November 5, 2022 Share Posted November 5, 2022 (edited) 32 minutes ago, llabnip said: Was there a reason the DragonFly used $FFFF as the hotspot vs the normal RAM banking (bit 5 of the banking write)? Was this to allow 1024K ROM games with 2x RAM? Not really. When Rafal did update for DF ask me if is worth it to add extra RAM compatible with our new SN76489 cart. I said, yes why not maybe someone will use it. BTW SN cart is using 6 bit for banking write and highest 2 bits for special reading banks (FlipX) Quote The 32kB cartridge address area was divided into 8 banks of 4kB each (banks 0-7). Four of them are constant, four are variable. They occupy the initial area of the EPROM memory. The rest of the 512kB EPROM memory is also divided into 4kB banks (banks 8-127). Banks: 2- $Axxx, 4- $Cxxx, 6- $Exxx (I will call them banks A, C and E) can be independently changed within the 0-63 bank, that is 256kB. To change the bank, write its number down to the starting address of the bank. Example: writing $1F to the address $A000 will cause bank A to be replaced with bank 31. From now on, any reference to the address $Axxx will read the data from bank 31. Banks A, C and E can be set to reverse the reading of data. This is controlled by the last two bits of the bank change data (D6-D7). 00 - normal reading - D = 76543210 01 - 160A mode - D = 10325476 10 - 160B mode - D = 54761032 11 - 320B & 320D mode - D = 01234567 Selecting the 01, 10 and 11 modes also causes that the bank is read from the back (the A0-A7 address lines are negated). Bank 5- $Dxxx (bank D) can be independently changed in the range of bank 0-127, that is 512kB. It is not possible to change the data reading order. Using 256kB EPROM instead of 512kB will cause bank D to be changed in the range of banks 0-63. The cartridge offers 2 banks of RAM, 16kB each, with the possibility of disconnecting the A8 and A9 lines (so-called EXRAM/A8 and EXRAM/A9). RAM is available at $4000-$7FFF. RAM control is possible by writing to the address $FFFF. D0- bankswitch RAM D1- EXRAM / A8 D2- EXRAM / A9 D0 = 0 - the first 16k bank D0 = 1 - the second 16k bank D1, D2 = 0 - RAM is working normally D1 = 1 - line A8 bypassed (state 0) D2 = 1 - line A9 bypassed (state 0) D1, D2 = 1 - lines A8 and A9 are bypassed (states 0) Once set, the RAM mode will be active until set to $FFFF again Edited November 5, 2022 by Eagle 1 Quote Link to comment Share on other sites More sharing options...
rj1307 Posted November 5, 2022 Share Posted November 5, 2022 (edited) Maybe I will answer : - before the CPLD update, DragonFly did not use an additional 16kB RAM, the upper memory was turned off, so it would be a pity to waste - ensures compatibility with the SN cartridge - the way of banking is easy to use The header does not contain this RAM banking information and is not needed in DF. @Eagle was faster Edited November 5, 2022 by rj1307 1 1 Quote Link to comment Share on other sites More sharing options...
rj1307 Posted November 5, 2022 Share Posted November 5, 2022 40 minutes ago, llabnip said: Was there a reason the DragonFly used $FFFF as the hotspot vs the normal RAM banking (bit 5 of the banking write)? What does "normal RAM banking" mean? How is it switched? Quote Link to comment Share on other sites More sharing options...
+wavemotion Posted November 5, 2022 Share Posted November 5, 2022 Just now, rj1307 said: What does "normal RAM banking" mean? How is it switched? The .a78 header bit for "banked ram" means that the cart acts like a SUPER RAM cart but that bit 5 of the bank write will switch up the RAM. In this way, the maximum bank is 0x1F so the game designer is limited to 512K of ROM as that next bit up will select RAM bank 0 or 1. The last 1942 binary posted here for the CC uses that RAM banking mechanism. Quote Link to comment Share on other sites More sharing options...
rj1307 Posted November 5, 2022 Share Posted November 5, 2022 I am interested in how the actual RAM bank switching takes place, bit 5 of the header only informs about it. Quote Link to comment Share on other sites More sharing options...
+wavemotion Posted November 5, 2022 Share Posted November 5, 2022 15 minutes ago, rj1307 said: I am interested in how the actual RAM bank switching takes place, bit 5 of the header only informs about it. Bit 5 of the .A78 header tells you it's banking RAM. Coincidentally, bit 5 of the paging write (i.e. the value you write to anywhere in 0x8000 to 0xBFFF) is the RAM bank to use (0 or 1). That limits the ROM banking to 32 banks (512K max). Quote Link to comment Share on other sites More sharing options...
rj1307 Posted November 5, 2022 Share Posted November 5, 2022 Ok I understood. In addition to 1942 for CC, has anyone else benefited from it? Quote Link to comment Share on other sites More sharing options...
+x=usr(1536) Posted November 5, 2022 Share Posted November 5, 2022 3 minutes ago, rj1307 said: In addition to 1942 for CC, has anyone else benefited from it? Any company that developed a version of it under licence from Capcom. Same for any licenced merchandising, etc. Quote Link to comment Share on other sites More sharing options...
rj1307 Posted November 5, 2022 Share Posted November 5, 2022 Translation error I asked if there is another game that uses this RAM banking? 2 Quote Link to comment Share on other sites More sharing options...
Eagle Posted November 5, 2022 Share Posted November 5, 2022 31 minutes ago, rj1307 said: I asked if there is another game that uses this RAM banking? I don't think so. Quote Link to comment Share on other sites More sharing options...
+wavemotion Posted November 5, 2022 Share Posted November 5, 2022 52 minutes ago, rj1307 said: Translation error I asked if there is another game that uses this RAM banking? 7800Basic has targets for these: 16k, 32k, 32kRAM, 48k, 128k, 128kRAM, 128kBANKRAM, 144k, 256k, 256kRAM, 256kBANKRAM, 272k, 512k, 512kRAM, 512BANKRAM, and 528k. All of the XXXkBANKRAM utilize the RAM banking using bit 5 of the page write (and will set the RAM banking bit in the A78 header) . However, only one test/demo (attached) that I've managed to find (courtesy of @RevEng) bankramtest.bas.a78 1 Quote Link to comment Share on other sites More sharing options...
AlecRob Posted December 1, 2022 Share Posted December 1, 2022 On 10/22/2022 at 2:17 PM, Silver Back said: This game absolutely needs a physical release. And really the name isn't that important. Use any of the suggested names, call it Plane Shoot Plane for all I care but it's so good it needs a proper release. Of course I understand why you don't want to but maybe consider making a few changes to where you do feel comfortable and make a few dollars on it. I really hope this game ends up in the atariage store or is available physically from somewhere... Not all of us are lucky enough to get ahold of crazy limited production run flash devices that sell out in a blink of an eye, lol. 2 Quote Link to comment Share on other sites More sharing options...
Trebor Posted December 1, 2022 Author Share Posted December 1, 2022 5 hours ago, AlecRob said: Not all of us are lucky enough to get ahold of crazy limited production run flash devices that sell out in a blink of an eye, lol. Concerto continues to be available... https://erstwhile-technologies-7800.square.site/product/concerto-cartridge/5 7800GD coming Q1 2023... https://twitter.com/TheRetroHQ/status/1595823940684873728 No limited production run for either device. 5 Quote Link to comment Share on other sites More sharing options...
+Pat Brady Posted December 1, 2022 Share Posted December 1, 2022 9 hours ago, Trebor said: Concerto continues to be available... https://erstwhile-technologies-7800.square.site/product/concerto-cartridge/5 7800GD coming Q1 2023... https://twitter.com/TheRetroHQ/status/1595823940684873728 No limited production run for either device. Note that Concerto, as of the current firmware revision, cannot load the full game (or other >128k games). 1 Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted December 1, 2022 Share Posted December 1, 2022 17 hours ago, AlecRob said: Not all of us are lucky enough to get ahold of crazy limited production run flash devices that sell out in a blink of an eye, lol. As @Trebor points out, Concerto is still available and @SainT's 7800GD should be out next year sometime. And to be fair, there was no "crazy limited production run" of @rj1307's Dragonfly. He had pre-orders open for months and plenty of time for people to add on once he got going. Production only stopped because pandemic-related supply chain disruptions made it impossible for him to get parts for more. It's not like anyone INTENDED to deprive anyone of anything. 🙄 7 Quote Link to comment Share on other sites More sharing options...
john_q_atari Posted December 1, 2022 Share Posted December 1, 2022 My observation is, if there is something you want, you need to be checking atariage enough throughout the year to see the announcement, and then make the purchase then and there and not wait for later or wait for funds to become available, etc. Its a hobby driven by people's limited time and finite resources. This translates into windows of time of availability. If you make the window, there usually is not a shortage and you can get what you like. For example dragonfly and Rikki&Vikki. But if you come by later and find something offered in the past then it probably is no longer available from the original source. It's just the way it is. 4 Quote Link to comment Share on other sites More sharing options...
Trebor Posted December 1, 2022 Author Share Posted December 1, 2022 22 minutes ago, DrVenkman said: And to be fair, there was no "crazy limited production run" of @rj1307's Dragonfly. He had pre-orders open for months and plenty of time for people to add on once he got going. Production only stopped because pandemic-related supply chain disruptions made it impossible for him to get parts for more. It's not like anyone INTENDED to deprive anyone of anything. 🙄 A "crazy limited production run" would be more along the lines of ~10 days or less, not the nearly 10 months DragonFly was available from December 7, 2020 until September 1, 2021. 1 Quote Link to comment Share on other sites More sharing options...
Jinks Posted December 2, 2022 Share Posted December 2, 2022 I wonder if he will ever make more? I would be interested once we come out of the upcoming depression. The alleged pandemic caused so much chaos and price gouging on all levels it is sickening. Quote Link to comment Share on other sites More sharing options...
+MarcoJ Posted December 2, 2022 Share Posted December 2, 2022 Just updated my Dragonfly to play 1942 longterm. Looking forward to some cracking sessions over the holiday period. The USB byteblaster is the simplest method, for those who are time/solder equipment poor. Cheap $10 off ehay. The dissassembly of the Dragonfly is nice, its a beautiful 3D printed design. The surprise was just how long the Altera Quartus software took to download and install, seriously budget an hour or more. Bloatware. The usb byteblaster needs drivers installed from the quartus install folder and the Dragonfly needs its power plugged in. Then, the actual CPLD upgrade takes mere seconds! There is also another upgrade done after the cpld, just have to place a file on the sd card and bootup the dragonfly. and that’s it. Looking forward to playing some sweet 1942. 3 Quote Link to comment Share on other sites More sharing options...
Silver Back Posted December 3, 2022 Share Posted December 3, 2022 Well the thing is I played 1942 on my concerto and while it's fantastic no matter how you play it, I noticed a difference between what I was playing and what zph showed on stream. If I get the new cartridge that's coming Q1 of next year will I get the dragonfly experience? Forgive me the name of the new one escapes me. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted December 3, 2022 Share Posted December 3, 2022 33 minutes ago, Silver Back said: If I get the new cartridge that's coming Q1 of next year will I get the dragonfly experience? Forgive me the name of the new one escapes me. “The new cartridge” is @SainT‘s 7800GD. Whether or not you get “the dragonfly experience” depends on whether that 7800GD supports Yamaha YM2151 sound in the same way Dragofly does, and supports the same cartridge binary size and configurations. I think people have said it will but until it goes on sale and we have units in hand, no one knows for certain. SainT generally posts on Twitter and I refuse to use that flaming dumpster fire at all anymore. 3 1 Quote Link to comment Share on other sites More sharing options...
Silver Back Posted December 3, 2022 Share Posted December 3, 2022 34 minutes ago, DrVenkman said: “The new cartridge” is @SainT‘s 7800GD. Whether or not you get “the dragonfly experience” depends on whether that 7800GD supports Yamaha YM2151 sound in the same way Dragofly does, and supports the same cartridge binary size and configurations. I think people have said it will but until it goes on sale and we have units in hand, no one knows for certain. SainT generally posts on Twitter and I refuse to use that flaming dumpster fire at all anymore. That's what it was thank you, 7800GD. Again playing on the concerto is fine but it's definitely a compressed experience. Unless I'm mistaken, but I know I made it as far as ZPH and I didn't see the things they did. So my biggest reason for purchasing 7800GD would be for the 1942 experience. I don't use Twitter either I don't see any personal benefit in doing so but I'm sure the news of the release will reach me. 2 Quote Link to comment Share on other sites More sharing options...
+playsoft Posted December 6, 2022 Share Posted December 6, 2022 Just to add that prior to the DragonFly CPLD fix, @SainT did test it for me on the 7800GD and it was fine. Regarding Concerto, currently it only supports games up to 144K but I was told that support for 256K ROMs will be added in the next major firmware release. 2 Quote Link to comment Share on other sites More sharing options...
AlecRob Posted December 8, 2022 Share Posted December 8, 2022 On 12/1/2022 at 6:28 PM, DrVenkman said: As @Trebor points out, Concerto is still available and @SainT's 7800GD should be out next year sometime. And to be fair, there was no "crazy limited production run" of @rj1307's Dragonfly. He had pre-orders open for months and plenty of time for people to add on once he got going. Production only stopped because pandemic-related supply chain disruptions made it impossible for him to get parts for more. It's not like anyone INTENDED to deprive anyone of anything. 🙄 I’m making sure this time to keep up with the 7800GD project and order one as soon as possible. I won't miss out this time. Quote Link to comment Share on other sites More sharing options...
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