IBM System/370 145 Manual page 185

Table 40.10.3. 1401/1440/1460 devices not supported by the DOS
1401/1440/1460
Em~aator
program
1445 Printer
Paper tape readers
Paper tape punches
Magnetic character readers
Optical character readers
DOS 1410/7010 EMULATOR SUPPORT
1404 Printer in cut card mode
7340 Hypertape Drive
Teleprocessing devices
Audio response units
The Model 145 DOS 1410/7010 emullator offers the 1410/7010 stand-alone
emulator user the advantages of inltegrated emulation already discussed.
Processor Storage Requirements
The size of the partition required for emulation depends on the
1410/7010 system being emulated. including standard and special
features, input/output devices, buffers, etc. The processor storage
required for the 1410/7010 emulator is equal to the combined sizes of:
• Simulated 1410/7010 storage. Each position of 1410/7010 storage is
simulated in one byte of Model 145 storage (for example, 20,000
positions = 20,000 bytes).
• Emulator routines required to emulate the 1410/7010 system
instructions, features, and I/O operations
• Tape, disk, and unit record buffers. The size and number of tape
and disk buffers are specified by the user.
Approximate minimum 1410/7010 emulator processor storage requirements
for emulation of a 1410/7010 system with unit record/tape operations or
unit record/tape/disk operations are shown below. For details about
processor storage requirements. see 1410/7010 DOS Emulator Q!! Models
145/155 (GC33-2005).
Emulated Operations DOS Partition size (bytes)
1410/7010 unit record and 6 tapes
1410/7010 unit record, 6 tapes.
25K + 1410/7010 storage size + buffers
34K
+
1410/7010 storage size
+
buffers
4 disks
The 1410/7010 CPU features and 1410/7010 I/O devices and special
features supported and the Model 145 devices used for 1410/7010
emulation are given in Tables 40.1,0.4 and 40.10.5. Table 40,.10.6 lists
the 1410/7010 I/O devices that are not supported.
Emulator performance will vary depending on user options, such as
number and size of buffers. the instruction mix of the 1410/7010
program, the format of tape files. and the priority of the partition in
which the emulator is running.
Emulator performance is improved. by:
1. Using double buffers and sp.anned record format for tape files in
lieu of single or shared bu:ffers and 1400 record format. (A
shared buffer can be used b:~ more than one I/O device.)
2. Using single buffers rather than shared buffers for disk files
3. Emulating unit record operaitions on a mag.netic tape or direct
access storage device
A Guide to the IBM System/370 Mode:L 145
175