When the Duo's Docked or MiniDocked, it's definitely the Duo's internal modem that's active via the Internal DAA relay/repeater/whatever thingie. I've mislaid my camera, but when I find it I'll post pics of the boards, it's certainly not a modem, but looks to have the oomph parts for driving the phone line from the data feed.Interesting question about the internal modem and whether or not if functions when docked.
What would be the equivalent of the rockwell chip on this board?
So essentially the Modem board just handles the step down and conversion from 48vAC, I’ll look through the developer notes some more and see if i can find an answer as to how the modem is operated when the Duo is docked.@Trash80toHP_Mini Very interesting, thanks for posting! Just the DAA then. So using a dock's "modem" must seemingly require the internal modem? That would explain why there's a line in the above diagram going from the MUX to the expansion connector.
@Challenger 1983 I believe the answer is that there isn't an equivalent. The pictured boards seemingly just contain the Digital Access Arrangement circuitry (step down x-former, signal conditioning, surge suppression, etc.).
Given that, the two biggest outstanding question I have are:
- Whether modem communication is possible when docked via one of those modules pictured above, but without an internal modem? For instance, the crummy soft modems (often called winmodems) of the day were just DAAs with some port interface requiring the CPU and installed software to emulate the hardware. Does the Duo potentially implement something similar?
- Did Apple provide some sort of non-ASIC (Rockwell or otherwise) equipped basic module in place of the modem version with just power/reset buttons if a Duo was ordered without the internal modem? I've never seen such an animal, nor have I ever seen a Duo without an internal modem, but my experience with this platform is pretty limited. This passage is lifted directly from the Duo "Getting Started" manual, which strongly suggests that not all Duos shipped with internal modems: "Apple offers an optional, low-power, internal fax/data modem for your computer."
With year-end at work and holidays at home, I haven't touched my Duo since posting the above I'm afraid. I'm hoping to find some time after Christmas to pursue the theory outlined above pertaining to the possibility of a built-in concession for a 3rd party traditional serial modem. I really with the Duo Developer's Note was more complete in that area. More than 2/3rds of the modem board's 50 pins are undocumented, some of which are clearly connected to the RCV144DPL "data pump".Any updates on this?
More than 2/3rds of the modem board's 50 pins are undocumented, some of which are clearly connected to the RCV144DPL "data pump".
Third party internal modems go all the way back to the faster than Apple's internal I got from APS along with max RAM upgrade and nice big little HDD for my first laptop love, a spankin' new PowerBook 100.
Doesn't surprise me at all, the modem board's the size of a PCMCIA card's PCB, no telling what they planned?
https://pdf1.alldatasheet.com/datasheet-pdf/view/167236/CONEXANT/RC144LD.html
Someone made an EtherNet MicroDock after all. Curiouser and curiouser. []
The Newer Technology Ethernet Microdock, while certainly awesome, is a bit less puzzling IMO, as the 152-pin PDS connector includes a complete SCSI pinout.
I think perhaps you keep missing my point here I don't believe they did or frankly even care if APPLE released such a device, only that they included a provision for one. Whether a 3rd party (e.g., Global Village, et. al) ever did is a question I haven't been able to answer though.I don't see any reason Apple would have bothered with a serial modem, they never updated the 14.4 modem they had from the start did they?
Take a look inside that Newer MicroDock I'm so jealous of, I'll bet a shiny nickel you won't find a SCSI interface setup, it'll be an 030 PDS NIC. []