Introducing (and interest check) AirTalk: Wireless plug-and-play LocalTalk dongles

[cheesestraws]

Yup. I don't know what it is - I think it must be the way that MacOS does power saving on the WiFi or something? Transfer rates from mini vmac over wifi are wildly inconsistent despite the application neither knowing nor caring that it's on wifi

 

[twelvetone12]

Do you guys think it would be possible to condense this on a modem adapter port for a l'ebook 100 series? My idea i just to drop the rs422 transceiver and connect the pic directly to the serial port. It would be basically like connecting AirTalk to a device with a serial cable, but never using rs422. I checked the powerbook 100 schematics and the both serial ports go to two ports on the serial controller ic, the only difference is that the external serial port has the 422 transceiver on it.
What do you think?

 

[cheesestraws]

Do you guys think it would be possible to condense this on a modem adapter port for a l'ebook 100 series? My idea i just to drop the rs422 transceiver and connect the pic directly to the serial port. It would be basically like connecting AirTalk to a device with a serial cable, but never using rs422. I checked the powerbook 100 schematics and the both serial ports go to two ports on the serial controller ic, the only difference is that the external serial port has the 422 transceiver on it.
What do you think?

So, you mean, take the single-ended output from the SCC and attach it straight to the single-ended input to the PIC? That feels like it ought to work, but obviously I haven't tried it myself. Would love to hear about it if you give it a try - have you found the schematics and so forth?

 

[twelvetone12]

Yup that is the idea! It is probably a huge overkill, but having a wireless powerbook seems fun! I have all the schematics and all the pieces, I'm just missing the PICs but hopefully they arrive soon.

 

[cheesestraws]

but having a wireless powerbook seems fun!

I think if you can get this to work, you will find other people want one too. It sounds like a lot of fun.

 

[tashtari]

I checked the powerbook 100 schematics and the both serial ports go to two ports on the serial controller ic, the only difference is that the external serial port has the 422 transceiver on it.

As I recall, only one of the two ports on the SCC supports LocalTalk, wouldn't that be the external one?

 

[cheesestraws]

As I recall, only one of the two ports on the SCC supports LocalTalk, wouldn't that be the external one?

I don't know about Powerbooks, but in the case of desktop Macs with a normal SCC, both ports support LocalTalk but the OS only makes one port appear. If you have either the drivers that come with the Internet Router installed you can use either, or I think there's a driver floating around somewhere that enables it for the modem port too.

 

[twelvetone12]

I studied the schematic a bit more: on the PB 100, the 85C80's SERIALA goes to the modem, all signals (except) are buffered via a 244, SERIALB just goes to the line transceiver (the schematic does not say what it is, I will open my unit later for curiosity) and then out to the port. So I think that unless there is a software limitation (scc's portb is hardcoded?) probably using a patched driver that shows the modem port could work.

Edit it is an LTC902CS, but I could not find a datasheet, in any case it does not make any difference since I would use the other port.

 

[cheesestraws]

using a patched driver that shows the modem port could work.

I'd suggest trying this one: this (attached; zipped diskcopy 4.2 image) is the official Apple driver that enables LocalTalk on the modem port as bundled with Apple Internet Router. Never used it on its own, but I don't see why it wouldn't work. It makes the modem port turn up in the Network control panel.

Probably worth trying it on a desktop Mac first .

 

[twelvetone12]

thanks! The extension loads and I can select the modem port, now I need to figure out a way to see if it actually works (I don't have another mac unfortunately), I guess if I hook up the scope to the TX pin I should see the initial LocalTalk messages when the computer powers up right?

 

[cheesestraws]

Yeah, see if you get something that looks like an attempted address negotiation on the Tx pin, I think.

 

[Andy]

Is the a program that can bridge LToUDP to EtherTalk? I have a couple of Macs setup with EtherTalk and that would let me connect a PowerBook over AirTalk and connect with them.

If not, maybe it wouldn't be too hard for me to write. Hmmmm.

 

[tashtari]

Is the a program that can bridge LToUDP to EtherTalk?

@sfiera 's MultiTalk can do it:

GitHub - sfiera/multitalk

Contribute to sfiera/multitalk development by creating an account on GitHub.

github.com

 

[Andy]

Ah thank you, that's perfect!

 

[DiskJockey]

So trying to get the right solution here (if there is one). RPi running netatalk 2.x- works. I'm gonna built tashtari's tashtalk when the parts arrive - yay. How do I get netatalk to use the tashtari? I see that tasktalkd uses the serial port for LT and creates a socket, but how does netatalk get configured to listen to the tashtari? So close...

And I don't need to use the ethernet interface at all. Just want service over the tashtalk.

 

[tashtari]

tashtalkd's function is to bridge between TashTalk's serial protocol and LToUDP - AirTalk does the same thing, bridging LocalTalk to LToUDP. Netatalk 2.x only speaks EtherTalk, so what you need is to bridge LocalTalk/LToUDP to EtherTalk. On a Mac, LocalTalk Bridge will do this; on an RPi, MultiTalk will do it. @sfiera is working on adding TashTalk support to MultiTalk so you can go from a TashTalk hat directly to EtherTalk but I don't know if it's complete yet.

how does netatalk get configured to listen to the tashtari?

I think you mean "TashTalk"... I'm "the Tashtari" and nobody listens to me. ;D