Adding an internal DIN 8 serial connector to the Apple Newton MessagePad 2100.

This is a rather low-tech hack which results in a built-in DIN8 serial port on the MessagePad 2000/2100. The particular connector chosen also includes a switch which, with some modification, can be used to trigger the NewtonOS dock/keyboard signal. Warning: This information is supplied without any guaranty of any kind. You risk seriously damaging your MessagePad if you use this information and you do so entirely at your own risk.

In a number of respects the SER001 solution from PCBman is superior being as it is a daughterboard which plugs cleanly into the J6 connector on the MessagePad motherboard. Update Revision B is now available. There is a user's perspective of the SER001 board here.

Given the nature of my hack I'll just provide the wiring locations and the part number for the connector I used. The location of each of the various serial port connections is shown in these photographs of the MP2100 circuit board: diagram 2 / bottom and (less useful) diagram 1 / top.
(The images can also be accessed directly here: diagram 2 and diagram 1.)

The connector used is the CUI Stack part, MD-80SMW, which is available from Digi-Key among other places. You can find drawings and information for this connector family on this page at the CUI Stack web site.

Note that the hole through which the connector will protrude is not rectangular but rather has sloped sides. Also, the top, back portion of the connector metal housing as well as some of the housing top near the front (end with the connector) will need to be cut away so that the connector will fit into the space. Note also that the connector's pins must be cut down to less than 1mm in exposed length; some sort of protection against wear and potential problems with the MessagePad casing interior coating would probably also be a very good idea. Finally the switch pins must be modified to be Normally Open in order to achieve the prodDockAttach pin function.
Again, this hack is a bad idea and you use any of this information entirely at your own risk.

© 2001, d.holmes
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