.... I ..,. .... I.Q (X) = 11 (I) .... txt U'1 =- . ca =- bI1 " H W c+ ...., (I) 0 11 U2 = J» Io.cS en ..... c+ .... (I) = • c+ (1) tat 11 0 11 I.Q = ..,. t'Ij n c+ J» ::x: ::s J» p, = P, I'd ..... 11 .... 0 = t:f \Q ..... d) • t:j (I) c+ (I) 11 • ..,. ts Pt c+ ..,. 0 ts I I ca 0 ..... CS • (I) .... External Interrupt PrOC8H--------------------------------------, OUTPUT ---------. If TOO clock comparator interrupt • unchain from TOO clock comparator VMBLOK • queue the related TRQBLOK PSA (prefix Storage Area) VMBLOK VMTERM RDEVBLOK I • place on dispatch queue • set new clock comparator request ............. VMGPRS If CPU timer interrupt ------------ • flag running user to be dropped from queue
VMFPRS If a Timer interrupt • if supervisor mode, ignore • otherwise, save machine status: VMOSTAT (for
operator) If interrupt from the Console Interrupt Button (External) • • Set the disconnect flag in VMBLOK • Halt any outstanding I/O • Clear any outstanding console requests • If the running user was not interrupted,
resume where left off by LPSW of External old PSW ..... -< External interrupt from control panel is used to disconnect
the system operator's terminal. The system operator may
reconnect at any other terminal via the LOGON command. ------ VMBLOK VMOSTAT X'10' VMTERM X'OO'

I-:Ij ..... Ul t1 (1) m "0 t1 0 \,Q t1 I» 51 H t:I ci' (1) t1 t1 C "C ci' I» t:I PI ...... ..... t:I \Q PSA • This is the entry point W to refh,ct SVC interrupts
(when DMKSVC could not reflect it) and to reflect privileqed instructions that
cannot be simulated by
DMKPRVLG Invalid operation code
is in GR O. The VMINST field of the VMBLOK contains
the image of the privileged instruction that caused the
interrupt • Program I nterwpt ----------------Process
Determine machine mode and cause of interrupt If in supervisor mode, go to DMKDMPDK to take CP dump ---..J------------- . ...r-..... If invalid operation, go to DMKPRGRF routine ••••••• ------- If recognizable privileged instruction, simulate it If privileged instruction is not recognized,
issue SVC 0 and dump CP If pag,ng exception, call DMKPTRAN to
bring page with requested address
into real storage. If proqram interrupt occurs in virtual problem mode, reflect the
interrupt back to the virtual machine _______ . ___ . _____ VMBLOI<: t VMINSTj SWPTABLE Virtual Storage OUTPUT ---------------.-, VMBLOI<: [VM_ r User's Page 0