Intel iapx 432 manual

iAPX 432 Interface Processor Architecture Reference Manual

To permit the I/O controller to function in the 432 system as well as in the Peripheral Subsystem, the IP provides an environment, and operators that it executes within this environment.· The environment is embodied in the system objects that the Interface Processor recognizes and manipulates, while the operators take the form of function requests issued by the IP controller and executed by the

IP. (Like a GOP, the IP performs other operations in response to interprocessor oammunications: these are normally transparent to the AP, however.)

The standard 432 object-oriented addressing and protection systems

underlie all IP facilities. The IP uses the same descr iptor-controlled, segment-based address develol;J1\ent mechanism

as the GOP. It performs type and ri.ghts checking identically. Addressing and protection apply to both the transfer of data through windows and the execution of functions.

Table 2-1 lists all 432 system objects and canpares the IP' s implementation of them with that of the GOP. For the most part these objects are handled identically by both machines; the variances noted in the table stem from the different orientation and design of the two machines. The IP does not inplement instruction segments, for example, because its Attached Processor takes care of instruction fetching.

IP processor, process and context objects are similar in purpose to the corresponding GOP structures, but are ~lemented somewhat

differently. Importantly, the processor and process objects are canpatible with the standard 432 processor and interprocess

oammunication facilities. The IP supports multiple process environments; a separate process can be associated, for example, with each Peripheral Subsystem device task. Each process has a single context object which defines the process's current access environment (i.e., the objects that are instantaneously accessible), and records status information.

2-2