Service manual

3-12 AlphaServer DS20 Service Manual
3.6 Device Interrupt Request Register (DIRn, n=0,1)
These registers indicate which interrupts are pending to the CPUs and indicate
the presence of an I/O error condition.
Address 801 A000 0280 CPU0
801 A000 02C0CPU1
Access RO
32
0
PK1418-99
31
58 57 56 5563
ERR
00
Reserved
IRQ1 PCI interrupts pending
IRQ1 PCI interrupts pending
Table 3-6 Device Interrupt Request Register
Name Bits Type
Initial
State Description
ERR <63:62> RO 0
IRQ0 error interrupts
<63> Cchip detected MISC <NXM>
<62> Pchip0 error
<62> Pchip1 error
RES <61:56> RO 0 Reserved
NXS <55:0> RO 0 IRQ1 PCI interrupts pending to the CPU