Guru Meditation
|
|
Guru Meditation is the name of the error that occurred on early versions of the Amiga home computers when they crashed. It is analogous to the black screen of death and the blue screen of death in other operating systems.
When a Guru Meditation is displayed, the options are to reboot by pressing the left mouse button, or to invoke ROMWack by pressing the right mouse button. (ROMWack is a minimalist debugger built into the operating system which is accessible by connecting a 9600 bit/s terminal to the serial port).
The alert itself appears as black rectangular box that located in the upper portion of the screen. Its border and text is red when it is a normal Guru Meditation, or green/yellow when it is a Recoverable Alert, another kind of Guru Meditation. The screen goes black, and the power and disk-activity LEDs may blink immediately before the alert appears. In AmigaOS 1.x, programmed in ROMs known as Kickstart 1.1, 1.2 and 1.3, the errors are always red. In AmigaOS 2.x and 3.x, recoverable alerts are yellow, except for some very early versions of 2.x where they were green. Dead-end alerts are red in all OS versions.
Guru_meditation.gif
A simulation of the Guru Meditation error message
This error is sometimes referred to colloquially as a "trip to India" or just "alert".
The alert occurred when there was a fatal problem with the system. If the system had no means of recovery, it could display the alert, even in systems with numerous critical flaws. In extreme cases, the alert could even be displayed if the system's memory was completely exhausted.
The error is displayed as two fields, separated by a period. The first field is either the Motorola 68000 exception number that occurred or an internal error identifier (such as an 'Out of Memory' code). The second can be the address of a Task structure, a special error code, or a meaningless value. It is never the address of the code that caused the error.
The text of the alert messages was completely baffling to most users. Only highly technically-adept Amiga users would know, for example, that exception 3 was an address error, and meant the user was accessing a word on an unaligned boundary. Users without this specialized knowledge would have no recourse but to look for a "Guru" or to simply reboot the machine and hope for the best.
Origins
The term comes from the early days of the Amiga corporation, and is partly an in-house joke. One of the early products produced by Amiga was the joyboard, a game controller much like a joystick but supposed to be operated by one's feet. It was sold with the skiing game Mogul Maniac for the Atari 2600 game computer. When the Amiga OS crashed, the programmer working with it would sit down cross-legged on the joyboard, trying to keep it in balance thus resembling an Indian guru.
The Guru Meditation error was removed from subsequent versions of the Amiga ROM (Kickstart), but some users choose to patch it back in.
External links
- Controller picture (http://www.atariage.com/controller_page.html?SystemID=2600&ControllerID=11)
- Guru Meditation (http://www.guru-meditation.net) (the introduction page contains an image of the effect)de:Guru-Meditation