Keyboard operating modes
Each key except the control keys has more than one function. Which function of a key takes effect is selected by a control key. There are two operating modes of the MZ-700 keyboard:
Base mode: The base mode is active after power on and if the BASIC interpreter is started. In this case all characters shown on the surface of the keys are usable ( ASCII characters, upper case letters, lower case letters if the SHIFT key is pressed coincidentally ).
Graphic mode: This mode is activated by pressing the key GRAPH. After pressing this key all characters shown on the front side of the keys are usable. If a key and the SHIFT key is pressed coincidentally, all characters shown on the right front side are usable, otherwise, if a key is pressed without using the SHIFT key, all characters shown on the left front side are usable.
To return to the base mode press the ALPHA key.
The graphic cursor will be shown while in graphic mode to enable you to distinguish the modes.
This is an example of key C functions:
Description of the control key functions
SHIFT: While in the base mode the key is used for lower case letters, while in the graphic mode the key is used for a character at the right front side of a key.
CR: Carriage Return is used to terminate the input line ( e.g. a character string ). The cursor will be set to the first column of the next line.
BREAK: The BREAK key code is set by the keyboard search routine. If SHIFT and BREAK is pressed coincidentally a program will be terminated and / or the inbuilt data recorder will be stopped.
GRAPH: Activates the graphic mode. The graphic characters at the front side of a key are usable. If a cursor control key function is pressed, the associated display code takes effect ( , , , and , ).
ALPHA: Returns from graphic mode to the base mode.
INST: If pressed, a space character will be inserted at the current cursor position.
DEL: The character shown before the current cursor position will be deleted and the following characters are shifted one character left.
SHIFT+CLR: The contents of the screen will be cleared and the cursor is set to the first column of the first line.
SHIFT+HOME: The cursor is set to the first column of the first line, but the contents of the screen remains unchanged.
The following function keys are not supported by the monitor 1Z-013A. The function keys are supported by the BASIC interpreter 1Z-013B.
SHIFT+F2: “DEF KEY(”
The associated string to a function key is automatically typed in into the BASIC interpreter input line if one of the function keys is pressed. You can redefine these keys for your own purposes by the BASIC command DEF KEY.