Lpc2000

Robert Adsett schrieb:

I jump in late, so sorry if I repeat an arguement:

> The question is: what extra advantage running in user mode and making calls 
> to a system mode kernal provides over an application running in system mode 
> making calls to a system mode kernal?

Even if there is no MMU/MPU which restricts access to memory, one vital
resource can be restricted: Interrupts.

In USR mode, you cannot modify the interrupt-bits whereas in SYS mode
you can.

Means, running tasks in USR mode lets the OS control the disabling of
interrupts.

-- 
42Bastian