Q: Why is it called IO?

A: Because the letters I and O look like the binary digits 1 and 0.

Q: Why has the border around the number display turned red?

A: This indicates that the current number display is not wide enough to display all the required digits. You can scroll the displayed content using the mouse or keyboard shortcuts.

Q: Why does the percent key produce incorrect results?

A: The % label is not used to indicate a percentage calculation, it represents the modulo operation (i.e. remainder after integer division). The % character is used to represent this operator in many programming languages.

Q: What keys do I click on to adjust the displayed mantissa/exponent?

A: These operations are only available using the up and down arrow keys on your keyboard to increase/decrease the displayed exponent value and adjust the displayed mantissa accordingly.

Q: Why is the Round To Nearest (Away From Zero) rounding type not available for 80-bit floating-point?

A: Floating-point calculations are performed using the Intel compatible Floating-point Unit of your computer's central processing unit and this does not support this rounding type. IO applies this rounding type in software for the other floating-point codings when it does the final conversion from the 80-bit result.

Q: Why are large digits only available for the detached number display?

Due to their relatively narrow widths, other windows would only be able to display an unacceptably small number of large digits.

Q: Why can't I see all the function keys?

A: There is a Window option that controls which floating-point function keys are displayed, by default the trigonometric and hyperbolic function keys are not displayed. This avoids screen space being wasted if you never use these functions.

Q: Why aren't the bitwise logical operators available for the fixed-point number coding type?

A: These operators are available for fixed-point codings, but only in bit pattern display mode. In word value display mode their use would require the mask operand to be entered as the numerical value for the required bit pattern, this would usually not be simple to determine.

Q: I've just pressed AC, but some of the number coding selection keys are still disabled, why?

A: Pressing the AC key clears all the stack registers but does not affect the memory registers. If any memory register contains incompatible contents for a number coding change then that change will be prevented (if specified in the calculator operation options) by disabling the appropriate key. Clearing the memory register(s) will enable the key(s).

Q: Is IO programmable?

A: Only in a very limited way. The expression editor can be used to effectively store a sequence of operations which may be re-executed quickly with different initial data values; however, only IO operations which have keyboard shortcuts may be specified.

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Q: What can't IO do?

A: IO does not provide features which are unlikely to be particularly useful to its intended user base, i.e., computer engineers/students/enthusiasts, such as: financial calculations, statistical data entry and analysis, complex number calculations, rational number calculations, numerical integration, equation solving.

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