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RaSCSI Development Thread
Posted by: Torbar on 2020-07-09 00:55:24 I did post in one of the Vintage Mac Facebook groups yesterday. That was me! Cool! I'm the one that posted the 50 pin connector version of the other scsisd clone. Cool to see that there are at least a few people with projects in the works for SD storage on old Macs
Posted by: kerobaros on 2020-07-09 15:02:04 How many gpio pins are left unused on the Pi? I wonder, if we have enough to run a small i2c bus, if we could add a small LCD or OLED and a few buttons to the board to switch CD images or the like. I've been dreaming of a FlashFloppy-style device for SCSI CD emulation since I got my Mystic a couple years ago.
Posted by: davidg5678 on 2020-07-09 21:50:14 Side note: I'm spending a bunch of time today trying to pull together a good documentation package for English Mac users. Feedback/comments/contributions are welcome! Your documentation is coming together very nicely! I look forward to being able to read it all when you finish. I have only ever had limited success understanding whatever it is google translate generates, so this will be a great alternative!
Posted by: landoGriffin on 2020-07-10 00:05:12 For the ethernet driver, someone developed some hardware that can be used with existing driver: I wonder how portable it is to RaSCSI… I haven't taken a look at the sources That is exciting!! The code might not be directly portable to the RaSCSI, but the understanding of the communication protocol is a huge win for the community! I'm running out of vacation time for this week, but this looks like something to tackle with my next vacation!! I'd make a comment about this being a weird use of my vacation from work.... but considering the crowd ;-)
Posted by: landoGriffin on 2020-07-10 00:32:34 How many gpio pins are left unused on the Pi? I wonder, if we have enough to run a small i2c bus, if we could add a small LCD or OLED and a few buttons to the board to switch CD images or the like. I've been dreaming of a FlashFloppy-style device for SCSI CD emulation since I got my Mystic a couple years ago. I thought the same thing! For this version, I broke out the i2c and VCC to a separate header to attach a super cheap OLED. I haven't got around to writing any code do do anything with it, but that shouldn't be too tough. You could also easily add a much larger screen, but I'm trying to watch the budget on this project 🙂 (Ignore the fact that my pin headers aren't soldered on straight....) As far as buttons, GPIO pins 4,5, 10-27 are used for the SCSI interfaces. GPIO 2 and 3 are used for the I2C interface. So, that leaves GPIO 0,1,6,7,8,9 that you could use for user control. You could also add a I2C GPIO expander and get as much I/O as you want.
Posted by: landoGriffin on 2020-07-10 04:24:50 Ok... wasn't as challenging as I thought it would be.... https://github.com/akuker/RASCSI/wiki/OLED-Status-Display-(Optional)
Posted by: kerobaros on 2020-07-10 10:14:41 Ok... wasn't as challenging as I thought it would be.... https://github.com/akuker/RASCSI/wiki/OLED-Status-Display-(Optional) View attachment 35455 AWESOME. 😀 How much are the parts for this, roundabout? EDIT: looking over the way you put together the service now. I had pretty much the same idea of using Python to both write to the OLED and control the rascsi process; great minds think alike!
Posted by: landoGriffin on 2020-07-10 10:46:07 AWESOME. 😀 How much are the parts for this, roundabout? EDIT: looking over the way you put together the service now. I had pretty much the same idea of using Python to both write to the OLED and control the rascsi process; great minds think alike! The components are around $40+ the shipping of the boards from China (which is around $20 to get them in a reasonable amount of time). Would there be any interest in pulling together a group buy? There are a couple things I would change/do differently... - Use through-hole for the 50-pin SCSI header. For some reason surface mount headers are much more pricey. - Create a daughter board to stack on top of this board, to allow SCSI chaining. Right now, this thing has to be the last device in the chain.
Posted by: kerobaros on 2020-07-10 10:50:30 Are you planning to make a revision of the board with the through-hole header? I'm not very experienced with surface-mount soldering, and while I think a small IC is probably within my abilities, I'm far less confident soldering up a 50pin SMD header, haha. I am probably interested in taking part in a group-buy regardless.
Posted by: PotatoFi on 2020-07-10 11:01:28 If the design gets to a point where it's fairly locked-down, I'd be happy to design a 3D-printed enclosure for it. I'll post the files when I'm done. I would just need a PCB and parts list. Here's my resume!
Posted by: landoGriffin on 2020-07-10 11:06:54 Are you planning to make a revision of the board with the through-hole header? I'm not very experienced with surface-mount soldering, and while I think a small IC is probably within my abilities, I'm far less confident soldering up a 50pin SMD header, haha. I am probably interested in taking part in a group-buy regardless. Ya, I'll change the 50-pin header to through-hole. The surface mount version isn't too bad to solder. It just takes a little time and patience. I do have a couple more boards that I could build up with the current design too.
Posted by: landoGriffin on 2020-07-10 11:08:50 If the design gets to a point where it's fairly locked-down, I'd be happy to design a 3D-printed enclosure for it. I'll post the files when I'm done. I would just need a PCB and parts list. Here's my resume! You're 3D design skills far surpass mine!!! That looks very professional! Do you guys thing there is a need for SCSI pass-through?
Posted by: NF_ on 2020-07-19 15:24:30 The components are around $40+ the shipping of the boards from China (which is around $20 to get them in a reasonable amount of time). Would there be any interest in pulling together a group buy? View attachment 35471 There are a couple things I would change/do differently... - Use through-hole for the 50-pin SCSI header. For some reason surface mount headers are much more pricey. - Create a daughter board to stack on top of this board, to allow SCSI chaining. Right now, this thing has to be the last device in the chain. Thank you for putting in the work on such an excellent project. I've just ordered all of the parts from DigiKey to build one. Most parts were in stock, just had to change the fuse for a similar one, along with the 0805 resistors. Easy. When shopping for somewhere to make the PCBs I uploaded gerber.zip to OSH Park but they report the design is missing a copper layer. Not sure what's up with that. I did put the order through with JLCPCB without issue. Thanks again.
Posted by: landoGriffin on 2020-07-19 23:58:44 Thank you for putting in the work on such an excellent project. I've just ordered all of the parts from DigiKey to build one. Most parts were in stock, just had to change the fuse for a similar one, along with the 0805 resistors. Easy. When shopping for somewhere to make the PCBs I uploaded gerber.zip to OSH Park but they report the design is missing a copper layer. Not sure what's up with that. I did put the order through with JLCPCB without issue. That's exciting! There is a problem with the design that will require you to do a cut/jump on the board. (Note: The fix is easier to do BEFORE all of the components are soldered on 🙂 ) https://github.com/akuker/RASCSI/issues/10 That's odd the OSH Park didn't like them. The ones I had made by JLCPCB went through fine. Some of the silkscreens didn't properly get applied, but I haven't taken the time to investigate. If you have the same issue - something that tripped me up during assembly was that U3 and U4 are reversed from U1 and U2. Without the silkscreen markings, its easy to mess this up. I do have 3 bare PCBs of my design that I'd be glad to ship to you or anyone else who wants them (If you'll cover shipping). I also have 5 of @K55's (aka fran-cap) boards along with some adapters to correct the swapped pins on his board. I'm happy to part with those for the cost of shipping. (Disclaimer: I haven't tried out K55's board)
Posted by: synchromesh on 2020-07-21 03:25:53 Great stuff guys, keep it up! 🙂 Regarding copper layers, silkscreens etc. I just came across this post in a topic about doing PCB panels in KiCad on another forum: Remember to add a copper layer to the front of the board, as JLC will only apply the black solder mask to copper. Dunno whether that helps.
Posted by: landoGriffin on 2020-07-21 05:06:31 Great stuff guys, keep it up! 🙂 Regarding copper layers, silkscreens etc. I just came across this post in a topic about doing PCB panels in KiCad on another forum: Dunno whether that helps. Awesome! Thanks! I mentioned to synchromesh in a PM that I'm probably going to do another board order mid-August. Feel free to PM me (or comment on here) if you want some. I can build them up for you (for a price 😉 ), provide them as a kit or just a bare PCB. (I do still have a couple bare extra PCBs of the current design)
Posted by: ScutBoy on 2020-07-21 06:27:37 I'd be in for a kit later this summer.
Posted by: rplacd on 2020-07-21 17:03:12 I'd also be in for a kit as well! Put me on your list.
Posted by: landoGriffin on 2020-07-22 01:10:10 Cool! This is motivational for me to keep moving bw🙂
Posted by: cheesestraws on 2020-07-22 01:12:59 I mentioned to synchromesh in a PM that I'm probably going to do another board order mid-August. Feel free to PM me (or comment on here) if you want some. I can build them up for you (for a price 😉 ), provide them as a kit or just a bare PCB. (I do still have a couple bare extra PCBs of the current design) Depending on price, I might well be interested in having you build one, if you're still up for it when you get the boards. Otherwise, a kit would also be good, but I've got enough projects at the moment...
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