Functional Information The functional diagrams that follow describe the prograa logic
associated with various control program functions. Not all CP functions
are described. These functional diagrams are meant to describe the CP
functions about which you may want aore detailed inforaation if you are
debugging, modifying, or updating CP. Figure 1 describes CP initialization process.
Figures 2 and 3 describe the real and virtual I/O control blocks used
by CP in its I/O control.
Figures 4, 5, and 6 show how CP handles SVC. external, and prograa
interrupts.
The CP paging function is described in Figure 7.
The CP spooling function (both virtual and real) is described in
Figures 8 and 9.
Figure 10 shows how virtual tracing is performed.
Figure 11 shows the steps involved in translating a virtual address
to a real address and gives an example of address translation.
The functional information contained in these diagraas is intended
for system programmers and IBM Field Engineering prograa support
representatives.
CP Introduction 1-13

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Mount devices check TOO clock
Log on operator Allocate Dump File start, perform that function
Go to Dispatcher
Wait for work r-----:------­ System's !ables