Intel iapx 432 manual Summary of IP Facilities

rnAPTER 2 CBJOCTS AND OPERA'lORS

This chapter describes the 432 environment as it appears to the I/O controller software. It :r;x:>ints out what the I/O controller can, and cannot, do in the 432 system. The first section broadly compares the facilities provided by the Interface Processor to those available on the General Data Processor. The remaining sections describe Interface Processor facilities provided for:

oaddressing and protection;

o objects for program environments;

o. facil it ies for asynchronous cannunication; o processes and storage resource management; o facilities for process scheduling and

dispatching.

Because a great many facilities are common to both pr.ocessors, this chapter aoopts the approach of describing IP facilities that are different or unique, and referring the reader to the iAPX 432 General Data Processor Architecture Reference Manual, (Order Number l7l860-00~fordescriptions of identical features.

2-1. SUMMARY OF IP FACILITIES

This section surveys the Interface Processor by comparing it to the General Data Processor. When reading this section, it is useful to recall the notion, introduced in chapter 1, of the AP/IP pair co-operating as a logical I/O processor. In this arrangement, the Attached Processor fetches instructions, provides arithmetic, logical, and flCM-of-control operations, and generates Peripheral Subsystem address references. The Interface Processor completes the logical I/O processor by supplying the faci.li ties for operation within the 432 system, plus the window mechanism for transferring data between the two systems. Windows are discussed in detail in chapter 3.

2-1