IBM System/370 Manual page 97

among System/310 models and is processed by recovery management
routines. The fixed logout area data indicates the reason for the
interrupt in the machine check code. The save areas in the logout
area preserve the status of the system at the time of the machine check
interrupt and contain the contents of the general purpose. the floating-
point, and the control registers.
The model-dependent CPU extended logout area begins at the address
specified in control register 15, which is set to decimal location
512 by an IPL or on a system reset. The length of this extended logout
area on the Model 165 is approximately 1000 bytes. The occurrence
of a logout to the CPU extended logout area is determined by the setting
of two extended logout mask bits in control register 14.
An
extended
logout can occur after a CPU error and when a hard machine check
interrupt takes place. This data can be recorded by recovery management
routines and the Processor Logout Analysis program can be used to
process this information at a later tiroe.
Decimal
locations
0
IPL PSW
FIXED AREA
8
IPL CCW 1
0-127
16
24
IPL CCW 2
• Model independent among
External old PSW
System/360 and System/370
32
SVCold PSW
models except for PSW bit 12
40
48
Program old PSW
• Processed by the
Machine check old PSW
control program
56
I/O old PSW
64
Channel status word - CSW
72
Channel address word - CAW
I
76 Unused
80
Interval timer
I
84 Unused
88
External new PSW
96
SVC new PSW
104
Program new PSW
112
Machine check new PSW
120
I/O new PSW
""I.-
128 128 167 Unused
.... L..
-
168
1
ChannellD 172 I/O extended log pointer
T
176
~--------------------1-7-6---23L-1-u-n-u-sed--------~~------~;l~---F-I-X-E-D-L-O-G-O-U-T--A-R-E-A--------
2321 Machine check code
T;~
76 - 511
240
J:t--------------------------------------------------f:i •
Layout is model independent
256
1""
240 - 255 Unused
::r
S t /370 d I
,J:"
;:L
among ys em mo e s.
1
Used to store status data for CPU retry operations Fields and bits used vary slightly
352
Xx
b d I
Floating point register save area y mo e
11-------------------------------------------------; •
Always logged on a
384
1
General purpose register save area
;r
machine check interrupt
448;.. Control register save area ; .Processed by RMS
512
I------------------------------------------------~~--------~-----------------
CPU Extended logout - 1000 bytes
(Pointer in control register 15
set to 512 at IPL or system reset)
1511
~----------------------------------------------~
CPU EXTENDED LOGOUT AREA
• Model dependent
• Logged on all hard machine
checks and first and seventh
CPU retry if not disabled
• Processed by Logout
Analysis Program
Figure 50.10.3. Model 165 fixed storage locations
15