Planning Considerations for CMS Planning Considerations for eMS The Conversational Monitor System (CMS) is a component of VM/370 that
provides a comprehensive set of conversational facilities to virtual
machine users. CMS operates only in a virtual machine, and together
with CP provides a time-sharing system suitable for program development,
problem solving, and general time-sharing work. CMS is a required component of VM/370. You must generate CMS in order
to support CPo This section contains the following information about CMS: • storage Requirements • Device Support • Libraries • Command Language • Program Language Facilities • Limited Support of DOS and OS • Disk and File Management • Tape Support • unit Record Support • Editing • Batch Facility • Saving CMS eMS Storage Requirements CMS requires virtual storage and auxiliary storage. A minimum of 320K bytes of virtual storage is required for a CMS virtual machine; this
virtual storage is distributed as follows: • CMS nucleus --128K
1. Loader -- 8K (for virtual machines with up to 384K of
1 virtual storage) I 12K (for virtual machines with more than 384K of
1 virtual storage) • User program AUXILIARY STORAGE area --184K (for application programs
disk-resident commands)
The CMS auxiliary storage requirements are:
or CMS • System residence for CMS -- 110 cylinders on a 2314 or 2319, 72
cylinders on a 3330 or 3333, 203 cylinders on a 3340 Model 35 or Model 70, or 29 cylinders on a 3350 in native mode. Part 1. Planning for System Generation 19

Planning Considerations for CMS • Resident disk space for application programs (CMS commands, user
programs, IBM Program products) --the amount of space needed is
program-dependent, and must be assigned by you. • Work space for application programs (CMS commands, user programs, IBM Program Products) --the amount of space is program-dependent, and
must be assigned by you.
Device Support eMS supports the virtual machine devices shown in Figure 2. r , Virtual Virtual Symbolic , IBM Device Address
1
Name Device Type 3210,3215,1052 cuu
2 CON1 System console 2314,231Q,3330,3340,3350 190 DSKO System disk
(read-only) 2314,2319,3330,3340,3350 191
3 DSK1 Primary disk
(user files) 2314,2319,3330,3340,3350 cuu DSK2 Disk (user files) 2314,2319,3330,3340,3350 cuu DSK3 Disk (user files) 2314,231
Q
,3330,3340,3350 192 3 DSK4 Disk (user files) 2314,2319,3330,3340,3350 cuu DSK5 Disk (user files) 2314,2319,3330,3340,3350 cuu DSK6 Disk (user files) 2314,2319,3330,3340,3350 cuu DSK7 Disk (user files) 2314,2319,3330,3340,3350 19E3 DSK8 Disk (use r files) 2314,2319,3330,3340,3350 cuu DSK9 Disk (user files) 1403,3203,3211,1443 OOE PRN1 Line printer 2540,2501,3505 OOC RDR1 Card reader 2540,3525 OOD PCRl Card punch 2401,2402,2403,2415, 181- 4 TAP 1-TA P4 Tape dri ves 2420,3410,3411,3420 1The device addresses shown are those that are preassembled into the CMS resident device table. You can change the virtual machine , addresses by using the CP DEFINE command. 12The virtual address of the system console may be any valid I multiplexer address. 1
3
The virtual device address (cuu) of a disk for user files can be any I valid System/370 device address, and can be specified by the CMS user , when he activates a disk. If the user does not activate a disk , immediately after loading CMS, CMS automatically activates the user's I primary disk (A-disk) at virtual address 191, the D-disk at 192, and , the Y-disk (a read-only extension of the system disk) at 19E.
L
Figure 2. Devices Supported by a CMS Virtual Machine Under CP, unit record devices and the system console are simulated
and mapped to different addresses and different devices. For instance, eMS expects a 3215, 3210, or 1052 type of operator's console, but many
terminals are 2741s or 3270s. Regardless of the real device type, the
virtual system console is a 3215. The control program (CP) of VM/370 handles all channel program modifications necessary for this simulation. eMS virtual disk addresses are mapped by CP to different real device
addresses. 20 IBM VM/370 Planning and System Generation Guide