System Technology - IBM System/370 145 Manual

MCRR error-logging routines for System/360 models will not
execute correctly.)
3. Programs that use the ASCII-mode bit in the PSW (bit 12). ASCII
mode is not implemented and this mode bit is used in System/310
to specify BC or EC mode of operation~
4. Programs that depend on the nonusable lower processor storage
area being smaller than 104 bytes. This area can be reduced to
512 bytes by moving the CPU extended logout area. (See Section 50.)
5. Programs deliberately written to cause certain program checks.
6. Programs that depend on devices or facilities not implemented
in the Model 145.
1. Programs that use model-dependent operations of the System/310
Model 145 that are not necessarily compatible with the same
operations on System/360 models.
8. Programs that depend on the validity of storage data after system
power has been turned off and then on.
Note that these are the same types of implementation-dependent
restrictions that exist for compatibility among System/360 models.
os
and DOS control programs are designed to support either BC or EC
mode of system operation. Support of Model 145 systems operating in BC
mode is provided by DOS Versions 3 and 4 and by OS MFT and MVT, each of
which is extended to support certain new System/310 hardware features
and I/O devices. EXisting DOS Version 3, OS MFT, and OS MVT control
programs generated for System/360 models can also be executed on a Model
145 operating in BC mode, if necessary (discussed in section 60:30).
Support of Model 145 systems operating in EC mode is provided by
DOS/VS, OS/VS1, OS/VS2, and VM/370, each of which is designated as
system control programming (SCP). All of these operating systems
support a virtual storage environment using dynamic address translation,
which operates only when the system is in EC mode. VM/370 supports a
virtual machine environment. User-written processing programs that
operate on a Model 145 in BC mode, under DOS Version 3 or 4, OS MFT, or
OS
MVT, can be used with DOS/VS, OS/VS1, or OS/VS2, respectively, with
little or no modification, as discussed in the optional programming
systems supplements (Sections 80 to 100). Hence, compatible growth from
a System/360 or a BC mode nonvirtual storage environment to an EC mode
virtual storage environment is provided.
SYSTEM TECHNOLOGY
The Model 145 uses monolithic system technology (MST) for logic
circuitry, as do other System/310 models. In addition, the
Model 145 embodies a significant technological advance in the area of
system storage implementation. That is, processor storage, as well as
control and local storage, is implemented using monolithic technology
instead of wired, discrete ferrite cores. The Model 145 is the first
IBM system to use monolithic storage exclusively.
Monolithic storage is similar in design to monolithic logic
circuitry, the latter representing a technological advance over the
solid logic technology (SLT) introduced with the announcement of
System/360. Since the technology associated with monolithic storage is
like that used to produce monolithic logic, monolithic storage can be
batch-fabricated.
10
A Guide to the IBM System/310 Model 145