68kMLA Classic Interface

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68net - a modern SCSI to Ethernet board
Posted by: Torbar on 2020-11-24 08:24:18 yes, right, the connector exists, I got this https://www.ebay.com/i/273425140933?chn=ps It looks like you'll also need a HD50 to db25 adapter for that, since the 68net uses db25
Posted by: ronan on 2020-11-24 08:26:10 It looks like you'll also need a HD50 to db25 adapter for that, since the 68net uses db25 I did not even notice 😛 So I guess designing a cheap (< $10) HD30 to DB25 could be a good idea 🙂
Posted by: Torbar on 2020-11-24 10:25:32 I did not even notice 😛 So I guess designing a cheap (< $10) HD30 to DB25 could be a good idea 🙂 Yeah, would definitely be a nice option. This one appears to be the correct adapter as well https://www.ebay.com/itm/HDI-30-pin-to-DB25-SCSI-port-adapter-for-legacy-Macintosh-systems-552/253843270894?epid=165012110&hash=item3b1a3cecee:g:xeAAAOxyqUpQ89G4
Posted by: Trash80toHP_Mini on 2020-11-24 11:16:00 …and I thought my ideas were a little whacky. :-D LOL! Whacky notions from outside the box for solutions to problems were my stock in trade. :blink: Now I play at it for fun.
Posted by: micheledipaola on 2020-11-24 12:21:48 Yeah, would definitely be a nice option. This one appears to be the correct adapter as well https://www.ebay.com/itm/HDI-30-pin-to-DB25-SCSI-port-adapter-for-legacy-Macintosh-systems-552/253843270894?epid=165012110&hash=item3b1a3cecee:g:xeAAAOxyqUpQ89G4 Shipping price to Europe is actually higher thant the adapter price, so... yes please, @ronan make that adapter too! 🙂
Posted by: ironborn65 on 2020-11-24 12:38:34 It looks like you'll also need a HD50 to db25 adapter for that, since the 68net uses db25 no problem, I have it
Posted by: Trash80toHP_Mini on 2020-11-24 14:39:56 Someone warned in another thread recently that those types of adapters are to be avoided. Strain relief is provided by Apple's adapter cables. I heartily agree with that. I'll add to that the fact they also lack the slide-lock mechanism of Apple's HD50 connector on the cables. That lock makes a world of difference, I never had great confidence in using my MICRO EN/SC in the field, which uses the same type connector as the inexpensive L-shaped adapters, but in the office or at home I didn't worry too much about it. However, my high dollar T-shaped adapter from APS (with termination/switch/LED ) is of very robust steel construction with a precision slot-lock connector built in that works by bump-friction. Not as good as an Apple cable, but better than the Micro EN/SC and inexpensive adapters. You'll also note that the squared off raised section of the inexpensive L-shaped adapter's (and expensive EN/SC's for that matter) lack of the triangular fillet of the Apple/APS connectors which provides a proper fit/larger loading area for angular stress in the vertical plane that counters downward force. Short/sweet version: be very careful about using those cheap adapters. I have several from various box lots I've snagged over the years. They're not as robust, but are probably good enough with careful use in a stabilized retro setup. But be careful, the longer the moment arm, the more danger of hot unplugging the SCSI connection a/o breaking something, like the solder connections on the PB logic board's connector. edit: I'll take some pictures to show the different connector configurations when I get the chance.
Posted by: wthww on 2020-11-24 16:35:51 Hello, I just wanted to say your project is really awesome and I appreciate it. Thank you for doing what you do, @ronan! The moderation team has cleaned up some off-topic posts in your thread. We apologize for that, and ask that everyone remember others when posting. Everyone can make a subforum-appropriate topic for projects they need to work on — no need to disrupt another forum-goer's thread! Thanks,
Posted by: ronan on 2020-11-25 01:08:42 Short/sweet version: be very careful about using those cheap adapters. I have several from various box lots I've snagged over the years. They're not as robust, but are probably good enough with careful use in a stabilized retro setup. But be careful, the longer the moment arm, the more danger of hot unplugging the SCSI connection a/o breaking something, like the solder connections on the PB logic board's connector. What do you mean by good enough ? What are the downsides of cheap adapters apart from hot unplugging ? 🙂 Someone warned in another thread recently that those types of adapters are to be avoided. Strain relief is provided by Apple's adapter cables. I heartily agree with that. I'll add to that the fact they also lack the slide-lock mechanism of Apple's HD50 connector on the cables. That lock makes a world of difference, I never had great confidence in using my MICRO EN/SC in the field, which uses the same type connector as the inexpensive L-shaped adapters, but in the office or at home I didn't worry too much about it. I see your point. Do you know if any of the good connectors you suggest are still on production ? 🙂 edit: I'll take some pictures to show the different connector configurations when I get the chance. Very good idea ! 😀 I just wanted to say your project is really awesome and I appreciate it. Thank you for doing what you do, @ronan! Thanks a lot for your support ! 🙂 The moderation team has cleaned up some off-topic posts in your thread. We apologize for that, and ask that everyone remember others when posting. Everyone can make a subforum-appropriate topic for projects they need to work on — no need to disrupt another forum-goer's thread! Yes I guess a little cleaning was needed, thanks !
Posted by: cheesestraws on 2020-11-25 02:21:09 What do you mean by good enough ? What are the downsides of cheap adapters apart from hot unplugging ? 🙂 I think it's mostly the physics of it: the cheaper ones tend to be big rigid things and these will put more strain on the connector on the powerbook, because they'll create a moment around it. The Apple ones tend to be smaller, and the better ones are flexible / cables. So you're much less likely to break something by sheer physics, if that makes sense.
Posted by: ronan on 2020-11-25 03:14:46 I think it's mostly the physics of it: the cheaper ones tend to be big rigid things and these will put more strain on the connector on the powerbook, because they'll create a moment around it. The Apple ones tend to be smaller, and the better ones are flexible / cables. So you're much less likely to break something by sheer physics, if that makes sense. That makes perfect sense. Any ideas of what's the name of the HDI-30 connector ? I can't find it on DK. Maybe it has another name ?
Posted by: Torbar on 2020-11-25 06:48:48 Any ideas of what's the name of the HDI-30 connector ? I can't find it on DK. Maybe it has another name ? http://www.pacificcable.com/Picture_Page.asp?DataName=SC38 According to this site, it's a non standard connector created by Apple, so not sure if you'll find it on Digikey. Not sure where all these 3rd party adapters were getting the connector though Worse case you might be able to measure the pitch of the pins and find another connector with the same pitch thats 6 columns x 5 rows and use that
Posted by: Trash80toHP_Mini on 2020-11-25 15:04:44 yes, right, the connector exists, I got this https://www.ebay.com/i/273425140933?chn=ps I did not know about that, nice ! I wonder if designing one would be worth it ? Pros : - fast to design - cheaper (especially because the one you suggest does not cheap to EU) If I can't find one to buy on ebay I'll do this little project I think 🙂 I managed to loose a detailed post yet again! 🙄 At any rate this might help you get off to a start with your PowerBook case project. Had a hunch and tore apart one of my L-shaped adapters, it uses a wire terminated part similar to or identical to the part ASANTE used. Straight up buying one of the cheapo adapters to cannibalize would likely be less expensive than the HD30 part you didn't find at DigiKey. I'd be very surprised if you can't find those or similar adapters on Ebay/Europe? Came up with several suggestions for your PB housing. If interested, search the Ports_Pinouts.PDF and I'll elaborate here, the Gamba2 link is dead. Alternately you can start a dedicated thread in hacks about a case for your board. I can post my research findings there and you can enlist someone from the 3D-printed objects gang to run with it so you can concentrate on board development here. Maybe Cory could move related posts from the beginnings of the PB application tangent to the new topic for you? That would keep them in context and do a bit of cleanup here? Can you export a DXF or other CAD file of your board, or an object oriented PostScript file from your board design package? Is there a Gerber to CAD file translation utility available? As a starter from my end, the termination wires might be long enough to be soldered into the inboard thruholes for the top half of your duplex DB-25 connector? Looks iffy, could you post a top view of your board? p.s. note the ridge/slot/hole implementation of the APS housing. You can also just see that the upper portion is a triangular filleted interface on one side as opposed to being a squared off inset on both sides as on the cheapo part, much more like the custom Apple connector. More pics to come at some point.
Posted by: ronan on 2020-12-01 16:04:36 A little post to keep you updated. I've been busy with work and personal time recently but here is a quick update. I have a few things to fix for rev B, mostly things around USB that prevented DFU to work correctly. But nothing hard to fix and that prevents me to work on the software side. The SCSI part is working well as you can see on the following screen 🙂 Next steps are implement the protocol to communicate with the driver on mac os. I'll keep you updated ! 🙂
Posted by: JCBone on 2020-12-02 00:22:05 Nice! So there is a generic driver in mac OS for SCSCI-Lan adapters?
Posted by: cheesestraws on 2020-12-02 02:06:07 Nice! So there is a generic driver in mac OS for SCSCI-Lan adapters? Nope. Each vendor basically did their own thing. @saybur reverse-engineered the NuovoLink protocol, though, and that work has been what people are building on top of.
Posted by: ronan on 2020-12-02 02:45:43 You're right @cheesestraws ! The fact that you see LAN on the screenshot is the fact that each SCSI device has a type https://en.wikipedia.org/wiki/SCSI_Peripheral_Device_Type and that's what SCSI Probe checks. But it does not mean mac os will support this device out of the box 🙂
Posted by: Dog Cow on 2020-12-03 13:49:54 Nope. Each vendor basically did their own thing. @saybur reverse-engineered the NuovoLink protocol, though, and that work has been what people are building on top of. I think that if you review the AppleTalk chapter in Inside Macintosh volume VI you'll find some discussion on the .ENET and .ENET0 drivers which would be applicable.
Posted by: Dog Cow on 2020-12-03 13:50:48 Next steps are implement the protocol to communicate with the driver on mac os. I'll keep you updated ! 🙂 Do refer to the AppleTalk chapter in Inside Macintosh volume VI for the standard driver interface, if you are not already aware of it.
Posted by: cheesestraws on 2020-12-03 14:03:46 I think that if you review the AppleTalk chapter in Inside Macintosh volume VI you'll find some discussion on the .ENET and .ENET0 drivers which would be applicable. I have that, and also Inside Appletalk. Do refer to the AppleTalk chapter in Inside Macintosh volume VI for the standard driver interface, if you are not already aware of it. Fortunately in this case there's an existing driver, none needs to be written.
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