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Duo 270c - Yay or nay?

mdeverhart

Well-known member
There must be something there with at least the power button on it.
Based on the service guide and the design note, I’m pretty sure it’s a PCB with the two power buttons on it (rear and keyboard), and a few traces. According to the design note, the pin out of the connector includes GND, unswitched 5V, a couple of keyscan lines to the power manager for the power buttons, and a CPU on/off signal to the power manager.

I’ve not seen one, but a crummy picture is here: https://www.macrepaircentral.us/powerbook-200-series-duo-210-duo-230-250-270c/series-upgrade.html

 

glay78

Well-known member
Any chance you've ever had it apart? I'm dying to see what the non-modem equipped Duos have in the expansion slot. There must be something there with at least the power button on it. Could provide some useful clues for my ongoing wifi modem replacement hack attempt :)
This is how one looks like.

1FE2B6FB-31C7-4AD1-A590-2AC8ACEF8FC3.jpeg

 

sutekh

Well-known member
Based on the service guide and the design note, I’m pretty sure it’s a PCB with the two power buttons on it (rear and keyboard), and a few traces. According to the design note, the pin out of the connector includes GND, unswitched 5V, a couple of keyscan lines to the power manager for the power buttons, and a CPU on/off signal to the power manager.


Thanks for the insight. I believe I've crawled through every Duo-related Developer's Note and Service Source document available, and the only pinout info I've encountered for the 50-pin SX20-50P-LTS-MH2-2T connector is on pg.58-59 of the general "Macintosh Duo System" Developer Note, however it appears to be incomplete. Do you perhaps recall where you ran across the pinout for the non-modem module? Thanks, and apologies to the Op for the tangent.

 

mdeverhart

Well-known member
@sutekh Unfortunately, the partial pin out on pgs. 58-59 of the DN is the only one I’ve found. I’ve been following your WiFi modem project with interest, and one of these days I want to spend some time with a multimeter to see if I can uncover some of the missing pins. I’ll definitely let you know if I come up with anything.

 

Challenger 1983

Well-known member
This is kind of off topic but I have a few questions about the duo's. The 270c has a ribbon cable connector on the bottom of the logic board, I have seen this on both a 210 and my 270c, what is this connector? is it for testing purposes. Another thing I witnessed recently after putting my DuoDock back together was a small icon of the DuoDock which replaced happy Mac on startup, what might this be?. 

I will post pictures about both the connector and the icon later on.

 
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