Compaq AlphaServer ES40 Informacje Techniczne Strona 372

  • Pobierz
  • Dodaj do moich podręczników
  • Drukuj
Przeglądanie stron 371
D-14 Compaq AlphaServer ES40 Service Guide
D.7
Interrupt Summary Register (ISUM)
The interrupt summary register (ISUM) is a read-only register that
records all pending hardware, software, and AST interrupt requests
that have their corresponding enable bit set.
If a new interrupt (hardware, serial line, crd, or performance counters) occurs
simultaneously with an ISUM read, the ISUM read returns zeros. That
condition is normally assumed to be a passive release condition. The interrupt is
signaled again when the PALcode returns to native mode. The effects of this
condition can be minimized by reading ISUM twice and ORing the results.
31 0
FM-05849.AI
4
SL
63 32
CR
14 345
7
9
8
1011
PC[1:0]
SI[15:1]
ASTU
ASTS
ASTE
ASTK
630 29 28 13 2
333839
EI[5:0]
Przeglądanie stron 371
1 2 ... 367 368 369 370 371 372 373 374 375 376 377 ... 443 444

Komentarze do niniejszej Instrukcji

Brak uwag