+Nathan Strum Posted July 23, 2016 Share Posted July 23, 2016 Fun fact, the coprocessor inside the Space Rocks cart is about 50x faster than the SNES. That would have been one expensive game cart in 1984! I think it would be an interesting project to build a cart capable of running Scramble or other DPC+/ARM games using only period components. (Well beyond my capabilities, but interesting nonetheless.) 1 Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted July 23, 2016 Share Posted July 23, 2016 I think it would be an interesting project to build a cart capable of running Scramble or other DPC+/ARM games using only period components. (Well beyond my capabilities, but interesting nonetheless.)Did ARM architechture even exist in the 80s? Might need to rewrite a lot of code... EDIT: The ARM came out in 1985, so Space Rocks is fair game, but will have to compete against the juggernaut NES! Quote Link to comment Share on other sites More sharing options...
Keatah Posted July 24, 2016 Share Posted July 24, 2016 (edited) Did they have 70MHz ARM processors then? Because I'm pretty sure that's the speed of Harmony and Melody..? - What I continue to find impressive is the low power consumption of ARM. Intel is a lost cause against these guys. Even back in the 90's ARM were doing chips running at 200+MHz while only consuming 1 or 2 watts at most! Edited July 24, 2016 by Keatah 1 Quote Link to comment Share on other sites More sharing options...
hizzy Posted July 24, 2016 Share Posted July 24, 2016 Did this come out yet? I didn't see it in the AA store Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted July 24, 2016 Share Posted July 24, 2016 Did they have 70MHz ARM processors then? Because I'm pretty sure that's the speed of Harmony and Melody..? - What I continue to find impressive is the low power consumption of ARM. Intel is a lost cause against these guys. Even back in the 90's ARM were doing chips running at 200+MHz while only consuming 1 or 2 watts at most! I'm wondering if those new overclocked 2.5Ghz quad core ARM CPUs they are cramming in those Android boxes compare to a mobile quad core x86-64? My laptop is AMD quad core 2.3Ghz excluding turbo speeds. I'm thinking perhaps the huge caches afforded to Intel/AMD processors may be contributing to the excess performance but also excess power consumption. It would be neat to see what one of these ARM juggernauts could really pull off when paired with high performance DDR3 and an OS that isn't walled off. You could throw in 32 parallel cores and it would still run cooler than today's top x86 desktop CPUs. Quote Link to comment Share on other sites More sharing options...
+FujiSkunk Posted July 24, 2016 Share Posted July 24, 2016 Did this come out yet? I didn't see it in the AA store Not yet! Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted July 25, 2016 Share Posted July 25, 2016 It would be neat to see what one of these AMD juggernauts could really pull off when paired with high performance DDR3 and an OS that isn't walled off. You could throw in 32 parallel cores and it would still run cooler than today's top x86 desktop CPUs. The x86 carry a lot of historic load with them. Internally they work like RISC CPU, while they externally they have to support 20 year old code. For sure this costs more energy than a modern design. Quote Link to comment Share on other sites More sharing options...
Keatah Posted July 25, 2016 Share Posted July 25, 2016 With today's tech there's no reason you can't do legacy and modern in the same chip. Extend it to the bus, too, if need be. Quote Link to comment Share on other sites More sharing options...
+johnnywc Posted July 25, 2016 Author Share Posted July 25, 2016 Did this come out yet? I didn't see it in the AA store This is scheduled for release sometime this fall! 1 Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted July 25, 2016 Share Posted July 25, 2016 The x86 carry a lot of historic load with them. Internally they work like RISC CPU, while they externally they have to support 20 year old code. For sure this costs more energy than a modern design. Dangit, I meant ARM juggernaut, but it came out wrong... Do ARM CPUs require more cycles than x86 to do the same work? Quote Link to comment Share on other sites More sharing options...
Neuronic Posted October 6, 2016 Share Posted October 6, 2016 I have to say that this is in my top 5 home-brew games! Nice work! If it comes out in cart form I will definitely buy it! 1 Quote Link to comment Share on other sites More sharing options...
YANDMAN Posted October 12, 2016 Share Posted October 12, 2016 WOW!!! Stunned, i go away for a little bit and come back and there is yet another amazing 2600 game. This scene continually blows my mind, amazing job. 2 Quote Link to comment Share on other sites More sharing options...
iesposta Posted October 12, 2016 Share Posted October 12, 2016 This is scheduled for release sometime this fall! Psst... This is still being worked on and polished! Have I said too much? Quote Link to comment Share on other sites More sharing options...
+Nathan Strum Posted October 12, 2016 Share Posted October 12, 2016 Psst... This is still being worked on and polished! Have I said too much? If Al's hit squad shows up at your front door, then you'll know. Quote Link to comment Share on other sites More sharing options...
Albert Posted October 12, 2016 Share Posted October 12, 2016 If Al's hit squad shows up at your front door, then you'll know. Quote Link to comment Share on other sites More sharing options...
+Cafeman Posted October 12, 2016 Share Posted October 12, 2016 Fun fact, the coprocessor inside the Space Rocks cart is about 50x faster than the SNES. That would have been one expensive game cart in 1984! How many times more powerful than an Asteroids machine? Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 12, 2016 Share Posted October 12, 2016 How many times more powerful than an Asteroids machine? The ARM is 70Mhz. Divide that by whatever clock speed the Asteroids machine uses. Also gotta take into consideration instruction sets, cycles per instruction, and memory requirements. Needless to say the ARM beats anything that could have existed in the 80s. Perhaps some guru could figure out what percentage of the ARM time is actually being utilized in Space Rocks. The Tournament Edition ROM could be used to test this since it pretty much maxes everything out in the Space Rocks engine. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted October 12, 2016 Share Posted October 12, 2016 At least we can calculate the theoretical maximum: 262 total lines - 203 displayed lines - 4 lines vertical sync = 55 ARM lines = ~21% = ~14.7 MHz effective clock speed. Quote Link to comment Share on other sites More sharing options...
Andromeda Stardust Posted October 12, 2016 Share Posted October 12, 2016 At least we can calculate the theoretical maximum: 262 total lines - 203 displayed lines - 4 lines vertical sync = 55 ARM lines = ~21% = ~14.7 MHz effective clock speed. But isn't the ARM also bus stuffing during the display? Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted October 12, 2016 Share Posted October 12, 2016 But isn't the ARM also bus stuffing during the display? I forgot. No idea how to calculate that. 1 Quote Link to comment Share on other sites More sharing options...
Keatah Posted October 12, 2016 Share Posted October 12, 2016 (edited) Heh.. you know.. when a homebrew of this quality comes out (it happens usually 2 times a year) I almost just want to download it. Then save it. Then take a drive to K-Mart or Toys'R'Us AND THEN PLAY IT. In order to simulate having to go to the store like in the 1970's. Or simply not download it myself, make the wife download it onto SD card and then bring it home later or something - another version of "going to the store" or waiting for mommmy or grandma to bring home new games. Yeh baby! Woot! Woot! Edited October 12, 2016 by Keatah 3 Quote Link to comment Share on other sites More sharing options...
+johnnywc Posted October 12, 2016 Author Share Posted October 12, 2016 But isn't the ARM also bus stuffing during the display? I'm not sure if Space Rocks is using it, but I don't think I'm using the bus stuffing technique in Scramble - I'm pretty sure the Harmony team is still working on that. I am using the data fetchers and FASTFETCH which allows you to update a register in 5 cycles using an 'immediate mode' that automatically gets the next byte, but I don't think that's referred to as 'bus stuffing' (Darrell can correct me on that one). I think bus stuffing is when the ARM is actually changing the data going into the registers with only a 'store' (e.g. sty GRP0), meaning you don't actually load the data in your kernel and then store it to a register. That will allow you to update a register in 3 cycles which I'm sure will allow even more advanced games to be developed. Anyway - back to Scramble. Yes we are working on finishing this up *very* soon, including packaging, and an announcement should be forthcoming! Thanks, John 5 Quote Link to comment Share on other sites More sharing options...
AtariBrian Posted October 12, 2016 Share Posted October 12, 2016 This game looks fucking awesome ... can I say fucking ? 3 Quote Link to comment Share on other sites More sharing options...
+Nathan Strum Posted October 12, 2016 Share Posted October 12, 2016 If Al's hit squad shows up at your front door, then you'll know. 1 Quote Link to comment Share on other sites More sharing options...
+SpiceWare Posted October 12, 2016 Share Posted October 12, 2016 But isn't the ARM also bus stuffing during the display? Nope, the BUS Driver is still under development. The only thing using it so far are some demos to test it out. I've released a couple of the demos for people to try on their Harmony carts - one's in "Bus stuffing" like The Graduate., the other's in A Programming CHALLENGE. I don't expect us to have the BUS Driver finished until sometime next year as we're investigating ways to make the audio support better. I suspect the first games to use it will be Draconian and Frantic, which will both be reboot to use BUS. Scramble, Space Rocks, and Stay Frosty 2 all use DPC+, which features data fetchers for faster data retrieval. These are like the ones found in the DPC coprocessor, used back in the day for Pitfall 2. DPC fetched data from ROM, DPC+ fetches data from RAM so it's much more flexible. We also added a fast-fetch feature to DPC+ which decreases access to the datafetchers from 4 cycles to 2. For what that means, here's a comparison of the code that must run on every scanline if you want to display just 1 multicolored sprite. Traditional code - 26 cycles per scanline: lda #SPRITEHEIGHT dcp SpriteTemp bcs DoDraw lda #0 .byte $2C DoDraw lda (GfxPtr),Y sta GRP0 ;+18 cycles lda (ColorPtr),y sta COLUP0 Activision's DPC - 14 cycles per scanline: LDA DF0DATAW ; 4 STA GRP0 ; 3 LDA DF1DATA ; 4 STA COLUP0 ; 3 Harmony/Melody DPC+ - 10 cycles per scanline: LDA #<DF0DATAW ; 2 STA GRP0 ; 3 LDA #<DF1DATA ; 2 STA COLUP0 ; 3 BUS - 6 cycles per scanline: STY GRP0 ; 3 STY COLUP0 ; 3 There's only 76 cycles per scanline, reducing how long it takes to update a sprite means you can make additional graphic updates one very scanline for a better looking game. 2 Quote Link to comment Share on other sites More sharing options...
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