K55 Posted May 3, 2017 Report Share Posted May 3, 2017 Figured I'd get this one started. I've just finished up the board design for an implementation for the RaSCSI device as seen here http://www.geocities.jp/kugimoto0715/rascsi/index.html Schematic: Board: Sorry about the messed up wires on the top, had to re arrange stuff to make the board layout easier. This design is going to use the 4 74ls641s. They run about $3 each and with everything else + pcb; $20 would be the at cost price. If anyone's interested I'll be ordering 10 (ish) copes tomorrow. I'd probably sell for around $30ish. The one benefit for this over the scsi2sd is that I think a raspi is more accessible and available to people than the other SCSI emulators on the market, and that this can be updated with new GPIO updates etc, and improved in software. Quote Link to post Share on other sites
K55 Posted May 3, 2017 Author Report Share Posted May 3, 2017 Side note this is the schematic I worked off of (in case it gets deleted): SCSI pinout: Quote Link to post Share on other sites
defor Posted May 3, 2017 Report Share Posted May 3, 2017 This design is going to use the 4 74ls641s. Glad to see you using SMT instead of DIP Two suggestions: - Add a second set of board mounting holes that aligns to the Pi, to allow for spacers to keep the SCSI pins from getting anywhere near the conductive surfaces of the HDMI port and similar. - Use a right-angle SCSI connector such that this actually might be able to be mounted somewhere where a HDD might fit that has cable clearance out the back, but none to the top. Quote Link to post Share on other sites
K55 Posted May 4, 2017 Author Report Share Posted May 4, 2017 (edited) V1.1 Update: now has 4 headers and a molex connector for power from the mac itself. Edit: This would work as long as you had enough clearance for the SCSI plug. I'm going to work on a right angle version but it'll probably push up the cost a dollar Edited May 4, 2017 by K55 Quote Link to post Share on other sites
Trash80toHP_Mini Posted May 4, 2017 Report Share Posted May 4, 2017 Beautiful! Another suggestion: use an ISA floppy/Zip power connector instead of MOLEX to keep the profile low. MOLEX connections are at a premium in Macs and FDD power takeoff/splitter cables seem to be a bit more compact/shorter. Quote Link to post Share on other sites
defor Posted May 4, 2017 Report Share Posted May 4, 2017 A little confused about the placement of the second set of mounting holes as they don't seem to line up with the PI mounting holes, or am I mistaken? Quote Link to post Share on other sites
K55 Posted May 4, 2017 Author Report Share Posted May 4, 2017 They're holes for the zero model, that's the aim anyway. I can fit in the regular holes, but its 2am and Im tired V1.2 with a right angle connector, had to rework the entire board, also switched to the mini 4pin floppy (thanks jt) Quote Link to post Share on other sites
K55 Posted May 4, 2017 Author Report Share Posted May 4, 2017 (edited) V1.3 With full size mounting holes. Still have to add some compact mac artwork, and fix the ground planes, and we should be done~~~ Edited May 4, 2017 by K55 Quote Link to post Share on other sites
olePigeon Posted May 4, 2017 Report Share Posted May 4, 2017 Any room in that design for a Jolly Roger with glowing red LED eyes? Quote Link to post Share on other sites
Trash80toHP_Mini Posted May 4, 2017 Report Share Posted May 4, 2017 (edited) LOL! I've already bounced another LED hack off K for that nifty little bit of prototyping real estate! Thanks for the suggestion, SMT LEDs right on board with a one piece printed coverplate might work out great for it. Edited May 4, 2017 by Trash80toHP_Mini Quote Link to post Share on other sites
joethezombie Posted May 4, 2017 Report Share Posted May 4, 2017 That's really cool. Put my name in for one. Can I ask what software you use to create these board layouts? I kind of want to get into hardware design, but don't know where to start with the software. Quote Link to post Share on other sites
olePigeon Posted May 4, 2017 Report Share Posted May 4, 2017 LOL! I've already bounced another LED hack off K for that nifty little bit of prototyping real estate! Thanks for the suggestion, SMT LEDs right on board with a one piece printed coverplate might work out great for it. Well, I designed the Jolly Roger that's used on a couple homebrew projects. Since I'm a liberal arts major, it was the only thing I could contribute to these awesome projects. So far, DougG3's original SIMM is my favorite implementation with the glowing red LED eyes. It's just too cool. I'd love to get a proto-clear lid for my IIci so I could see it all the time. Quote Link to post Share on other sites
olePigeon Posted May 4, 2017 Report Share Posted May 4, 2017 Does this have to be connected to a Rasberry PI? Or can it work like a SCSi2SD? Can I update it without a Pi? Quote Link to post Share on other sites
Trash80toHP_Mini Posted May 4, 2017 Report Share Posted May 4, 2017 (edited) I love the red glow of mine too, but when I'm around them my boxes the hoods are almost always popped. Love your design. Workin' on a Clear IIfx lid, got access to a CAD/CAM milling rig? Liberal arts major here too/fine arts minor, it's not a bug it's a feature! Also frees the mind from conventional fetters, especially at a Jesuit school! Edited May 4, 2017 by Trash80toHP_Mini Quote Link to post Share on other sites
K55 Posted May 4, 2017 Author Report Share Posted May 4, 2017 Does this have to be connected to a Rasberry PI? Or can it work like a SCSi2SD? Can I update it without a Pi? Its made to work with any pi B+ fowards, so the 2,3, zero etc. Makes things flexible. We'll see about software once I get the HW in and can work with the original dev's drivers. JT would breakout points for the activity led be ok with you? Quote Link to post Share on other sites
defor Posted May 4, 2017 Report Share Posted May 4, 2017 I personally wouldn't even have bothered supporting the zero, considering how slow it should be, given the 1MiB/sec was measured off a Pi3, and GPIO speeds are bound to the cpu speed, but who knows.... I'm working on a different style project using RaSCSI so don't worry, I won't be overlapping once I get my pcb finished- put me down for one of your boards as well though. Quote Link to post Share on other sites
Trash80toHP_Mini Posted May 4, 2017 Report Share Posted May 4, 2017 Sure, just put in thru-holes for header pin installations for: Power 5V & 3.3V are available on the board, correct? HDD Activity Fill up the added real estate on the side with a prototyping area just for kicks. Breaking power and HDD activity out to a header will give oP the chance to print up some 3D skull-n-pistol sticky badge dongles for his LEDs. Put the Logo Dongle on wire wrap wire and thread the leads out through the power LED light tube opening and he'll be a happy camper. Somebody can figure out how to drive 'em at 3.3V/whatever whenever the computer is on then and kick 'em up to the full 5V whenever there's a disk access blip fed to an adapter circuit in the proto area. Maybe just a couple of gates? He'll be friggin' thrilled. ]'> Do I see any mechanism for SCSI Drive ID settings? Quote Link to post Share on other sites
K55 Posted May 5, 2017 Author Report Share Posted May 5, 2017 Sure, just put in thru-holes for header pin installations for: Power 5V & 3.3V are available on the board, correct? HDD Activity Fill up the added real estate on the side with a prototyping area just for kicks. Breaking power and HDD activity out to a header will give oP the chance to print up some 3D skull-n-pistol sticky badge dongles for his LEDs. Put the Logo Dongle on wire wrap wire and thread the leads out through the power LED light tube opening and he'll be a happy camper. Somebody can figure out how to drive 'em at 3.3V/whatever whenever the computer is on then and kick 'em up to the full 5V whenever there's a disk access blip fed to an adapter circuit in the proto area. Maybe just a couple of gates? He'll be friggin' thrilled. [ ] Do I see any mechanism for SCSI Drive ID settings? ID is set in software, still looking at the software side, will probably understand it at some point, SCSI isn't that complicated V1.4: Added in breakout header for JT, tided up some minor errors, and added in snazzy artwork. It's probably done at this point, so I'll order it tomorrowish and expect it to be here the 1st week of june approx. Quote Link to post Share on other sites
Trash80toHP_Mini Posted May 5, 2017 Report Share Posted May 5, 2017 Sweet! Quote Link to post Share on other sites
defor Posted May 5, 2017 Report Share Posted May 5, 2017 with the wider board, Is it going to run into the ethernet/usb jacks? Quote Link to post Share on other sites
K55 Posted May 6, 2017 Author Report Share Posted May 6, 2017 with the wider board, Is it going to run into the ethernet/usb jacks? It goes under the raspi, but it should be fine V1.5: I got the correct floppy power connector from the SCSI2SD guy so its thinner now (aka around the width of a raspi B+-2-3) Just ordered this version, so I should have 10 or so copies by next month. Quote Link to post Share on other sites
Themk Posted May 6, 2017 Report Share Posted May 6, 2017 (edited) What PCB order service did you use K55? Also, what are you doing your designing in, what EDA program are you using? Edited May 6, 2017 by Themk Quote Link to post Share on other sites
K55 Posted May 6, 2017 Author Report Share Posted May 6, 2017 CAD, but the old version. I'm trying to learn OrCAD and Altium Designer also. Its really you use what you find most conformable. They all arent super user friendly, but altium designer has the best toolkit for really testing a design (with rules and the like). I order almost all my pcbs from dirtypcbs, or electrow usually. This time I used electrow. Quote Link to post Share on other sites
Themk Posted May 6, 2017 Report Share Posted May 6, 2017 I've been using KiCAD, it's okay but I am looking for something else kinda. IDK. Thanks for the info. Quote Link to post Share on other sites
Trash80toHP_Mini Posted May 6, 2017 Report Share Posted May 6, 2017 (edited) Do you use free versions that are good up to certain board size limits for open source projects like this? What are max sizes for PCB layouts and board fabrication within that licensing scheme? Most projects seem pretty tiny to me. I'm used to seeing a lot of DIP 74LS and discrete thru-hole components on boards no smaller than a short 8-bit ISA card. 100mm x 100mm seems tiny. Edited May 6, 2017 by Trash80toHP_Mini Quote Link to post Share on other sites
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