Specifications

6-40 I/O Port
Table 6-13 Hose Status Signals
Table 6-14 Down Hose Packet Type Codes
Signals Meaning
I/O port interrupts the CPU(s) on the indicated transitions, if interrupts are enabled
CBLOK L
PWROK H ERROR L
X
X
L
L -> H
H -> L
H
X
X
H -> L
I/O adapter just finished powering up - Adapter ready
to receive and process packets. I/O port generates in-
terrupt to CPU(s) on transition of PWROK.
I/O adapter detected power failure. I/O port generates
interrupt to CPU(s) on transition of PWROK.
I/O adapter detected a fatal error. I/O adapter enters
quiescent state and ignores further hose traffic. I/O
port generates interrupt to CPU(s) on high-to-low tran
-
sition of ERROR.
Meaning of hose signals when read through the I/O port’s status register
CBLOK L
PWROK H ERROR L
L
H
L
L
H
X
L
H
H
X
X
L
I/O adapter ready - Adapter ready to receive and proc-
ess packets.
Hose cable is disconnected or bad, or I/O adapter is not
plugged in.
Hose cable OK - No power on I/O adapter module.
I/O adapter detected a fatal error or I/O port is in in-
ternal diagnostic loopback mode.
DND<15:11>
1
DND<1:0>
2
Packet Type
00000
00010
XX10X
00110
01110
00110
01110
11110
XX
XX
XX
00
00
01, 10, 11
01, 10, 11
XX
INTR/IDENT Status Return
DMA Read Data Return
Mailbox Command
Dense Window Read Command
Dense Window Write Command
Sparse Window Read Command
Sparse Window Write Command
Memory Channel Write
1
Encoding during first cycle of Down Hose packet.
2
The SPC<1:0> field ( DND<1:0> ) of the first cycle of a window command packet deter-
mine whether it is dense or sparse. If this field is 00, then it is dense. If this field is not
00, then it is sparse.