USB<->RS485 Dongle w/free Mac OS 8/9, OSX drivers

[Trash80toHP_Mini]

http://www.ftdichip.com/Support/Documents/DataSheets/Cables/DS_USB_RS485_PCB.pdf

Duo Modem Bay WiFi Dongles come to mind of course, but I'm thinking more along the lines of general purpose wireless KBD/Rodent dongles lately. IIRC there were ASCII KBD and Serial Rodent hacks for the Mac's serial port dating all, or most of, the way back to the 128k.

If nothing else, serial Comms between an Intel Mac and a 128k might prove interesting.

Not all that inexpensive @ $25.00 per from DigiKey . . .

. . . maybe it might be an interesting toy in the hands of someone competent however? :?:

edit: if it could work in a Duo Modem Bay, I'd think it might work in any Powerbook or Portable's Modem Bay.

 

[Gorgonops]

Just double-checking Trash... you're not thinking that this dongle would be somehow useful in interfacing some other USB device to an old Mac, are you? (Remember the power tool + accessories analogy: A USB peripheral is *not* a USB host.) Hiding one in a Duo would be of somewhat limited utility unless you wanted to, I dunno, keep it in there with one of those snap-retract USB cables so you'll always be ready for a null modem session with another Mac.

 

[bigmessowires]

That sounds right. This chip would let you connect via USB to a host computer, so that computer could pretend to be an RS485 device for the vintage Mac.

 

[Trash80toHP_Mini]

I was thinking in terms of a Microcontroller card inside the Modem Bays of PBs a/o maybe on a Modem Card in a Luggable acting as the host, heck you could install the kluge inside a Mac 128k for Serial port speed WiFi . . . in dreams of course . . . but who cares just how fast WiFi would be on any serial port limited pre-PCMCIA Mac . . . or that Quixotic 128k WiFi quest?

I'm guessing from the specs that the drivers are only for the serial connection from the Mac end of things, though they might be for hosting on a PCI architure Mac?

I could be full of S#!%*!+ again, but I thought it was worth a mention. Worst case bad dream scnario of serial WiFi under OS8 works for me. :approve:

edit: ISTR the PowerBook serial port 10bT adapter running a bit faster than your average serial to Ethernet bridge, at least there's a driver to crib from in that case.

Dunno, incompetent noob here. :I

 

[Gorgonops]

Okay... although I'm not sure why you picked this dongle necessarily. RS-485 isn't really what you'd want to interface to the Mac's serial port anyway. It's technically RS-422, but lacking the ability to do SDLC (IE, Localtalk) you're limited to RS-232 speeds/protocol. (USB adapters that support SDLC are mucho, mucho bucks, we had a thread about those recently.) There are plenty of microcontrollers (chips/complete boards) that have RS-232 built right in. (Well, you might need to add a dingus to go from ttl to rs-232 signal levels when you're talking about raw microcontroller chips.)

In any case, if you're talking about sticking this in a Duo with no USB the presence or lack or drivers for this thing for OS 8 is immaterial; you'd have the *serial* side hooked up, not the USB side, and the drivers are for the USB side. If you did stick a little microcontroller-controller-WiFi dingus interfaced via serial inside your Duo somewhere (the guts of something like this, for instance) then you'd need to use apropos software for it to set up a "serial" network connection, which would probably translate to using a PPP dialer to "dial" into a computer somewhere on your local network over Telnet.

 

[Trash80toHP_Mini]

DANG it ,g! You gotcha'd me again there, I forgot all about the LocalTalk twist on that PB Adapter . . . :-/

There seems to be an RS232 board capability as well, or is that a second board in the front/back diagrams in the .PDF?

But, again, I'm thinking of a microcontroller board running the Linux drivers acting as the host and adapter for wireless USB peripheral I/O a/o those Wifi or Bluetooth Dongle Dingi.

I'm still dreamin' until this reaches the nightmare stage. :beige:

 

[FireBlade93RR]

sorry to but in unannounced, but i was also interested in adding some connection to my duo's

something like this https://www.spark.io maybe

 

[Trash80toHP_Mini]

The more the merrier and IDK if I've said it yet, but welcome aboard! :beige:

 

[FireBlade93RR]

Thanks, been following the forums for a long time, just recently registered.

 

[Gorgonops]

Wow, that Spark thing is... sort of creepy the way it ties you to a third-party web API and servers that could go away anytime and basically says "trust us!" when it comes to security.

In any case, it's just a small microcontroller connected to a module with a custom firmware that instead of offering "serial bitstream-centric" access to a UART port it gives you an interface to twiddle GPIO pins through. (Which is actually counterproductive in this case.) There are lots of serial-centric modules floating around that would probably do (just a sample) for setting up a PPP network connection to an appropriately configured server computer. (I've read the data sheets for a few, in general you treat them sort of like a modem. What you'd need on the Duo end is a PPP dialer that allows you to set up a very-custom dialer script.)

The "holy grail", of course, would be a small embedded computer that was powerful enough not to just tunnel serial over a TCP port, but to act as the PPP endpoint and to "proxy-nat" through a WiFi connection on the other side. (thus dispensing with the need for a "support server".) I'd guess that in fact the embedded CPUs in most of these modules could in theory handle that but I doubt any of them supply the source code necessary to hack that functionality into them. For that you'd probably be stuck looking for the smallest embedded system that runs Linux (or something) that has a serial port and a WiFi chip. I dunno how much space you have to work with, but there might be some candidates out there.

 

[bbraun]

Unless I'm missing something, the internal modem connector of the duos doesn't speak serial. It's basically soft-modem signaling and the different modem cards were for different countries with different telephone certifications. There's no rs485, and no tx/rx that I could find on the dev notes. We went over this once before, but if there's new information on that connector, I'm all for it.

 

[Trash80toHP_Mini]

The Modem bay is available, absolutely useless cubic, serial would piped in there from elsewhere. The Modem free power board form factor rulz! :approve:

 

[Bunsen]

The "holy grail", of course, would be a small embedded computer that was powerful enough not to just tunnel serial over a TCP port, but to act as the PPP endpoint and to "proxy-nat" through a WiFi connection on the other side. / the smallest embedded system that runs Linux (or something) that has a serial port and a WiFi chip.

http://8devices.com/carambola-2