The IBM AT didn't come with an operating system with a lightweight premptive multitasking kernel capable of being used for real time applications.
I learned quite a bit about operating systems by disassembling the Amiga exec and other libraries with a debugger. The code was elegant and efficient, modular and well thought out. Putting the core of the operating system in ROM was a good idea for the time as it freed up most of the RAM in the system for application use - an important design choice when machines were only shipping with 512KB to 1MB of RAM.
I learned quite a bit about operating systems by disassembling the Amiga exec and other libraries with a debugger. The code was elegant and efficient, modular and well thought out. Putting the core of the operating system in ROM was a good idea for the time as it freed up most of the RAM in the system for application use - an important design choice when machines were only shipping with 512KB to 1MB of RAM.