Source code and layout for an Apple Newton MessagePad ROM board reader/writer.
The Newton ROM Reader reads the contents of Apple's MessagePad MP2x00 ROM boards. Besides the well know US and German ROM, we were able to read prototype ROM boards for further research.
Using the alternative Flash ROM Board, the ROM Reader can also program the Flash chipd and create new ROM Boards with patched or alternative operating systems.
Assembling the Programmer requires some advanced soldering skills. The pin headers must be soldered around the outside of the board facing down. They must be flush with the PCB on the top, or the ROM board will not fit.
The SD Card connector is soldered to the underside of the board. The top of the connector should be insulated using an ample amount of tape, avoiding a short circuit with header pins on the Arduino.
The DIMM memory socket is more difficult to solder. The pin pitch is relatively small. To make sure that the soldering is correct, the first tool to run in the Programmer should be the short circuit test.
The last solder part is easy, but must not be forgotten. It's a jumper that set the power to 3V. Connect the two eyes marke with an asterisk (*).
| Lower left corner of the PCB
|
| ooo ooo
| ooo **o
| ...... ........
+---------------------
The Programmer board should be mounted on an Arduino Due. It MUST NOT be used with an Arduino Mega 1280/2560. The Mega runs at 5V and will likely destroy any ROM, Flash, or SD card inserted into the Programmer. The Due runs at the required 3V. If the large USB-A port of the Arduino blocks access to the SD Card slot, you have the wrong board!
The Programmer communicates with the user via USB connection to the Programming port. No extra power connection is required. There is no extra software for the Programmer. User must use a serial terminal program to connect to via the USB line (57600bps/baud 8N1).
The source code comes in an Arduino sketch. The "SdFat" library must be
installed within the Arduino system, and SPI_DRIVER_SELECT must be set to 2
in the <SdFat.h> header file.
Load the .ino file and set the board to 'Arduino Due (Programming Port), then chose the right port from the Tools > Port` menu.
Open the serial monitor Tools > Serail Monitor and press Ctrl-U to upload
the firmware to the Programmer.
The Programmer PCB was designed with Eagle CAD 7.7.0 Stadard Edition. It's a two layer board with no exeptional requirements.
The SO-DIMM 72 modules are not very common anymore and are somewhat hard to find. The SD Card socket is a standard SMD part. Pin headers shoudl be square shaped to fit the Arduino receptables well.
The Programmer writes a 90's style menu over the USB serial port connection. Functions can be selected by typing the command key and Return. Most commands will require confimation of the status of the programmer. Type "ok" and Return to confirm your setup.
s: Check all connectors on the board fro short circuits. This tool helps verifying that there are no bridges in the DIMM connector soldering.e: Check if the Flash memory is empty (all addresses return 0xFFFFFFFF).c: Erase all sectors in the selected Flash area.r: Program the Flash with the content of the binary file named "ROM" which should be copied to the SD Card in the programmer.