System initialisation

Introduction and Overview

During system initialisation the OS goes through a number of phases. During these phases there may be indications of the progress for diagnostic purposes. The sequence of colours displayed on VIDC systems for Kernel 9.70 is given below. Other systems may produce different colours and, due to continuous development, colours may be changed in future versions.

Technical Details

System initialisation

ColourMeaning
BlackSystem has not initialised at all - or display is not connected.
CyanMemory detection is in progress
GreenMemory detection complete, about to enable MMU
Light greenMMU enabled, about to enter RISC OS

RISC OS

ColourMeaning
WhiteDebug environment initialising (not usually seen in production OS versions)
Dark greyHardware vectors being initialised
Dark blueEarly system memory initialisation
Light blueOS page table initialising
Light pinkOS page table initialisation successful
Light magentaDynamic area, abstraction layer, and system memory area initialisation.
Mid greyMain OS initialisation - NVRAM reset check, and verification; Software vector table initialisation; IRQ handlers initialisation; Environment handlers initialisation; VDU subsystem initialisation; High level environment initialisation; Kernel keyboard dispatcher; PBTS structure initialisation; Page table initialisation; Module initialisation
RedOnly occurs within the above sequence if a NVRAM reset is detected.
BlackVideoHW for the system has initialised, this is usually accompanied by a flashing cursor. If the cursor stops flashing, this indicates that a ROM, or expansion card, component has either failed or is taking a long time to initialise.
<beep>Operating system has initialised successfully and is about to begin boot from disc, or through boot menu. This is followed immediately by the display of the RISC OS banner.

The positioning of the colour indicators within the system initialisation has been selected to identify the most common failure points. A correctly functioning system should not display any of the above colour indicators for more than a second. Any system failure during start up may indicate hardware failure. This may range from poorly fitted components (for example memory or expansion cards) to damaged or missing components. Check all user accessible components before contacting your supplier.