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I recently started working on a I suppose, with all the computer cards removed, and a buffered cable, the same board could be connected to the CART/ECI or the PBI. I only just started designing the bus, though, but I specifically copied the CART/ECI so it's easy to use existing boards, like the SysCheck for RAM and ROM. During testing, or always if you can't or don't want to build the ROM and RAM cards.

Lovebyte weekend is over. Here's v6. Added two more spares to the fast/unbuffered bus, which is now 2x4 instead of 2x3. Also helped in sourcing parts 2x3 is hard to come by. Today I ordered ten pieces of each (2x4, 2x13, CART/ECI[2x15, 2x7] , 2x6). Price was less than €0.50 a piece for 50 card edge connectors. When I recieve them, I can check the spacing on a perfboard. Goal is a 20x20cm board with a power circuit and 10 slots 650 mil wide (for socketed chips overhang), and slots that's less than 17.5cm long. Backplane Computer Bus v6.pdf

Here are my entries: Inner Groove Static Buzz - 32 bytes https://files.scene.org/get/parties/2021/lovebyte21/32_byte_intro/inner-groove-static-buzz.zip Disruptors Ready - 32 bytes https://files.scene.org/get/parties/2021/lovebyte21/32_byte_intro/disruptors-ready.zip Just X and Y - 64 bytes https://files.scene.org/get/parties/2021/lovebyte21/64_byte_intro/just-x-and-y.zip SID or Without U - 128 bytes (C64) My second program on the C64 ever. https://files.scene.org/get/parties/2021/lovebyte21/low_end_128_byte_intro/sid-or-without-u.zip Chill64 - 256 bytes (C64) My very first programming attempt at the C64! https://files.scene.org/get/parties/2021/lovebyte21/low_end_256_byte_intro/chill64.zip The Road To Bach - One Page - 256 bytes https://files.scene.org/get/parties/2021/lovebyte21/low_end_256_byte_intro/the-road-to-bach--one-page.zip The Groove - 256 bytes https://files.scene.org/get/parties/2021/lovebyte21/low_end_256_byte_intro/groove.zip And last but not least, and it was my best scoring entry, my collab with F#READY. He did the effect, I did the music. Diamonds Are Forever - 256 bytes https://files.scene.org/get/parties/2021/lovebyte21/low_end_256_byte_intro/diamonds.zip Source will appear on github in the (near?) future

Another day, another PDF. I decided to add two more spare signals to the I/O and MMU signals connector. One spare seems not enough. You never know what the future might bring. Some other design decisions I made: All connectors should be different. Not a chance you can plug in something wrong. Except for a cartridge the wrong way around Big fat front/back markings on the silkscreen. Replicated CART/ECI and the PCB footprint should be compatible. You can plug in a CART/ECI card (SysCheck FTW!), or a single cartridge. Even C= shells (SIDE, etc...) should fit. As per DrVenkman's concerns, the unbuffered clocks and the fast bus are on a separate connector that does not need to be routed to more than 3 slots, although another one or two slots would be nice. But not the full backplane. I added a size column in mil. The whole bus, with proper gaps to fit CART/ECI etc..., is now 17.018 cm. I imagine the backplane to be 20cm x N, where N is >= 20 cm Backplane Computer Bus v5.pdf

TL;DR If you need the money or shelf space, sell it. If not, keep it.

OSC --> GTIA --> FPH0 --> ANTIC --> PH0 --> SALLY --> PH1 and PH2 A buffered PH2 is fed back to both GTIA and ANTIC. And indeed, PH1 is used for the charge pump that feeds the color adjustment pot back to the GTIA. Trying to have that kind of synchronization with externally generated clocks is out of the question Here's my latest PDF I grouped signals by known "groupings". Hope I orientated the ECI right in regard to the cartridge port. See page 3. Added some colors, too Edit: each of those cards could be replaced by something else, as long as they continue providing the clocks back and forth. A new CPU card, new graphics cards, ... Backplane Computer Bus v4.pdf

79 signals, and a proposal how to layout the signals on several edge connectors. AN/Unbuffered clocks -- 2x20 free -- Cartridge port -- SIO Bus Now the question is, how to layout the remaining 39 34 signals on 2x20? Any ideas? I hope it is clear that I'd like to separate the fast bus, because of earlier raised concerns. SIO has its own connector, so SIO only cards could be made. Cartridge bus has its own part of the slot. And 2x20 left for the rest The CPU card, for example, does not need to connect to the SIO connector. But a SIO2SD card would only need the SIO part of the backplane bus. And an R-TIME8 cart could live on just the cartridge part. How to exactly layout the PCB that makes this possible, even with legacy carts, is a discussion for later Edit: Wrong file. Attached the right one now. Backplane Computer Bus v3.pdf

Oh, found a missing signal! SIO COMMAND. Pretty important

Here's how I did it. Not sure if it would fit on the alternate stackpole keys. This should be the last revision I printed 100-fold kcadapt2-stackpole-v4.obj

What do the keycaps look like at the underside? I created stackpole-to-cherry adapters for 3D printing. It also brings the keys up! I could share the design.

Every slot is general purpose slot I might decide though to put the AN Bus and the Fast clock at the end of the slot and route them to only three or four slots for CPU, ANTIC and GTIA.

To be honest, I have no idea how bus capacitance will affect this design. There are backplane computers that run at 8MHz, with clocks on the backplane bus. I was hoping that a 4-layer 2mm backplane with power supply and ground/power planes, would be stable enough for up to 20cm long signals. Each card with ground fills, and they won't be big like EISA cards

The idea is that the PIA board indeed has a pin header to bring out the signals to the connectors at the outside of the casing. Similar with the keyboard signals. Could be TransKey, could be lotharek's new USB AKI device. And the GTIA signals on a pin header. I tried to keep signals that are only relevant to one particular task/card out of the bus. No joystick ports, no keyboard matrix, no GTIA csync/color/lum. There's all the audio signals though. GTIA buzzer, SIO Audio IN, and Pokey L/R. One could opt for a dedicated audio mixer card, or let the Pokey card do the mixing. Edit: or a case could be designed where the joystick connectors etc.. are soldered on the PIA card directly, and are connected to the outside world. But that's a discussion for later. Question: which of these signals would benefit from being on the backplane bus and could be used by different cards? Convince me, and I'll add it I added /REF and SYNC myself because I can imagine that, for example, a DMA card could need them.

Hi, Several times I have coined the idea of an Atari Backplane computer, so let's discuss this a bit. I would like to avoid bikeshed discussions and feature creep. The first thing to do, is to design the backplane and determine which signals should be available on the bus. My idea is to put every Atari VLSI chip on its own card. That means, for example, that the AN Bus should be there for communication between ANTIC and GTIA. There could be a separate card for CPU, ANTIC, GTIA, ROM, RAM, MMU, POKEY, PIA, MIDI, SDrive, etc. Swapping cards should be a breeze. A backplane computer is basically a 1090, but with the computer on the same board. Hmm, like a 400/800 Here's my proposal for the backplane bus. What do you think? Any signals missing? Discussion about connector type, or grouping of signals, etc... is an issue for later. First determine the bus signals. I'm at 78 signals now Backplane Computer Bus.pdf

That's due to his alternate tuning. Perfect 8ths, perfect 5ths (how about 3rds?), and tune to the bass notes. Distortion A does not need a well-tempered tuning with A=440Hz. Tune to the bass notes! 👍 It could be nice to calculate which keys are best suited to the (fixed) Dist C frequencies, and then create just intonated Dist A tables for those keys.

I happen to have looked into how the Atari keyboard works last year when I got the idea to recreate ALP keyboards. Yet another unfinished project And now there's this USB solution. Not a true Atari keyboard ofcourse, but if this works with a BT receiver, that would be very cool. Computer on the big screen with DVI/HDMI, me on the couch with a wireless keyboard

Help is a normal key, even though it looks like a console key.

With @mytek's designs at hand, it is possible to create a computer similar to the 800. A main board that provides power, maybe some logic or buffering, and a master bus with multiple edge connectors. Put all five VLSI chips on a separate plug-in card. Sixth card with MMU, seventh card with RAM, eighth card with ROM, and a few spare slots. Base board 20x20cm. Slots 200 mil by 10cm plus 400 mil spacing for chips hanging off the boards. With that width, you can handle 60-70 channels on the bus that rules them all. One ore two standard edge connectors. Plug-in cards are 10x5cm or 10x10 cm, with pin headers at the top to bring out the signals to the connectors. You can have at least 12 bus connectors on 20x10cm, have 6 more on 10x10cm, and leave the other 10x10cm for bus drivers, power, etc... The master bus should consist of at least the address bus, data bus, all clocks, including fast clock/bus between GTIA and ANTIC. SIO. Audio. MMU lines. Perhaps more

Note that with a single Pokey, you lose two channels (channel 3+4) for MIDI communication. A stereo upgrade would be needed to reach at least the channel count of MIDIjoy. But it's a nice project. Something I was considering doing myself somewhere in the future, but there are so many other projects Good you already found the midimon source code. I agree with MyTek that it could function as a starting point. Rip-out the printing part and start playing pokey notes instead

I always wonder, how do you keep this dust free? Do you go over it every week with a vaccuum cleaner? Or dust rags?

I always wanted my monitor on top of the drives, but apparently that wasn't a good idea BITD with CRT monitors Nice setup!

Binning this whole thread would not be the solution IMHO. YMMV. Somehow, I never run into arguments with emkay anymore. I changed the way I communicate with him. Sure, he has issues. So have I. And a lot of other AA members.

Possibly, but a nice feature you mentioned before was arpeggios in the pattern domain, instead of the instrument domain. Converting such a GoatTracker file to RMT will lose that, because RMT does not have that feature. The only way RMT could handle that is if each pattern line is exactly one frame. But you still cannot edit the chords/arpeggios within RMT.

Shorted a whole motherboard on the shielding: check. Misalligned a chip by 1 pin in a 40 pin socket: check. Or the keyboard connector: check. I never got beyond a bicycle But I once I could really have used some help of The Bicycle Repairman. You know, you fix a tire, forget to check the outer tire, put it all together, inflate it, and pssssssssssssssst

Other projects or life got in the way But I'm glad you found use in my RE efforts. Back in 2012 my idea was to write converters to the RMT format. Last year emkay and I shortly discussed a GoatTracker to RMT converter, but it seems there's not a huge library of GoatTracker files available, so that would be wasted effort.