4

Next: Moves itself to RAM for actual work   Previous: Processor and Board specific   Contents: Index


Usually starts from ROM (Flash)

When a CPU starts, it has certain preset values in its registers, it usually knows nothing about on board memory. It expetcs to find program code at a specific address, this address usually points to ROM or Flash, this is the beginning of bootloader code. First task of boot loader is usually map the RAM to predefined addresses. After RAM is mapped Stack pointer is setup.

This is the minimal setup required, after that the bootloader starts it's work.


Next:
Previous:
Contents:
Moves itself to RAM for actual work
Processor and Board specific
Index
Prepared by Ori Idan Helicon technologies