1. A 64-bit computer^Wcalculator design

    In my public key cryptography project, this is deadly needed: non-electrical manual computer^Wcalculator, so that I can manually compute digital signature.

    Here is a figure to show the basic design of its register of 64-bit.

    +-----------------------------------------------+
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |                                               |
    |-----------------------------------------------|
    |                                               |
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    +-----------------------------------------------+
    

    It's 3-3 abacus. You may know that Japanese abacus adopts 1-4 system, while Chinese …

    more »
  2. Flying Stone Mini 55 Test Plan

    We need to specify the test plan to manufacture the board. In order to encourage designing and manufacturing by yourselves, we show our test plan for Flying Stone Mini 55 here.

    As of August 2014, free software tool to program MCU's flash ROM is not yet ready (for reset signal …

    more »