Porting Unix to the 386: A Practical Approach

William & Lynne Jolitz

Started open source UNIX.

Appeared in part as a 17 article magazine series in 1991-1992.

Documented the "how, what, why, who, when" of porting BSD to the 386.

Done while BSD was becoming "open source".

Porting Unix to the 386: A Practical Approach - interrupt priority levels

interrupt priority levels:

Interrupt Priority Level Management

Part of the specification also details the interrupt control mechanism that allows device interrupts to be blocked/unblocked and caught by device drivers interrupt handling code.