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external bridge for localtalk to usb/unix?
Posted by: chelseayr on 2022-01-17 08:34:30
while realizing that when I said 'network' I had meant ethernet but since localtalk was mentioned in the thread nevertheless (re stylewriters in the network category of forum) it got me to start thinking a bit about this...

given that you have open access to low-level io relatively speaking and , I wonder how involving it could be to make a 'raw' localtalk-to-usb adapter
(that is the adapter itself simply repacks the data between both bus methods and its up to the host cpu to do the actual work, aka softmodem sort of style. beside given that its a very low bitrate that even a lowend P-M laptop would barely ever notice this task)

I'm not saying that it would be equally as useful as native localtalk&systemos but it might open up certain things such as sending txt files between a lone old/notold pc and a gaggle of non-ethernet vintage macintoshes etc?

anyway thats just my own very-snowed-in morning thoughts on this, anyone else want to debate this? 🙂
Posted by: NJRoadfan on 2022-01-17 08:51:40
You might as well run a RS-232 serial cable at that point. Only about half as fast as LocalTalk, but simple to setup. Remember that LocalTalk needs the AppleTalk networking stack setup and run in order to work. Serial just needs a terminal problem on the client Mac.

Your idea can be made possible with TashTalk though: https://68kmla.org/bb/index.php?threads/tashtalk-single-chip-localtalk-interface.38955/
Posted by: chelseayr on 2022-01-17 12:54:29
njroadfan good point there but then quite a number of setups would need a second bridge in name of rs232-usb so I dunno if its just easier to simply have a single localtalk-usb bridge in the first concept instead. I mean just for laptop examples, the T40 quotes "Note: There is no Serial or PS/2 port" .. I'll have a good look at the tashtalk and see tho so thanks
Posted by: cheesestraws on 2022-01-17 13:01:06
@tashtari and I both were thinking about this independently as it turns out: the easiest way by far would be to use a TashTalk wedged onto the front of a USB UART. There are open source designs for a USB->serial adapter, and you could just take one of those, rip out the RS232 drivers and replace them with a TashTalk, the necessary RS485 drivers, and magnetics for isolation. Eminently doable and not hard thanks to the existence of TashTalk, but unsure how useful it would be.
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