Additional options for the Astrolabe Channel numerical pointer, together with not allowing memory location 0 to be used.
William Overington
Copyright 2002 William Overington
Saturday 2 February 2002
This document provides an overview of two additional options which may but need not be included in any particular implementation of an Astrolabe Channel numerical pointer. They are accessed by using the VK_LEFT button or the VK_RIGHT button when the accumulator of the Astrolabe Channel numerical pointer contains the value zero.
The implication of this is that memory location 0 cannot be used for storing data nor for retrieving data, so the basic design of the Astrolabe Channel numerical pointer is slightly modified by the provision of these additional options.
The VK_LEFT button used when the accumulator of the Astrolabe Channel numerical pointer contains the value zero enters a calculator, so that input buttons then have the values described in the document about the calculator code sequences. Depending upon the intended usage of the calculator, the calculator may be implemented either as free standing in its actions as between itself and the Astrolabe Channel numerical pointer, simply being accessed via the Astrolabe Channel numerical pointer so as to save on scarce button resources when the calculator is being accessed from a main program in which both a calculator and an Astrolabe Channel numerical pointer are being used; or the calculator may be implemented as being used in conjunction with the Astrolabe Channel numerical pointer so that the calculator may be used to calculate a value that is then sent back to the Astrolabe Channel numerical pointer for use in, say, a mouse event.
The VK_RIGHT button used when the accumulator of the Astrolabe Channel numerical pointer contains the value zero enters an escape area, from which other options may be accessed. No other options are defined at the present time, the escape area being made available so as to provide for future expansion should it seem desirable at a later time.
Astrolabe Channel
Copyright 2002 William Overington
This file is accessible as follows.