Simulated I/O and controllers:

The combination of channel, controller and disk are simulated for disk models 3330 and 3350. The model, size and content of the disk are kept in a segment provided by the user.

The IBM 370 BC mode architecture and the non-translate portions of EC mode are the only modes supported. Specifically, Virtual Memory and Dual Address Space operations are not supported. Storage key operations (ISK, SSK, SPKA, etc.) are simulated, but memory is not protected, so programs that depend on detecting protection violations will not run correctly.

B220 - Instruction issued by CMS initialization
This instruction was added to CMS initialition between SP4-409 and SP4-412. Our SP4 VM treats is as an operation exception. The routine within CMS that is using it issues a B2200027 instruction. The 2 and 7 appear to be register references. R2 appears to be some kind of input parameter. R7 appears to be a page aligned output buffer. If the instruction returns CC0, then DMSINS waits for an external interrupt (enabled w/ CR0 mask 00000200, defined in XA only for diagnose to control program communications). When it occurs, it initializes the halfwords in the simulated OS CVT at offsets X'4C' and X'4E'. These are documented as "reserved" in the VS2 field engineering handbook.

SSK - Supported to the extent of saving the value set

ISK - Only returns the last value set with SSK

EXecute of privileged instruction - Fully supported

SSM - Fully supported

LPSW - Does not permit loading of an EC mode PSW with translate on

DIAGnose instructions as follows:

0 - Store Extended Identification - Supported

4 - Examine Real Storage - Gives privileged operation exception

PRINTER is a key that will receive any printer spool files that have not been held or spooled to self. The protocol matches the protocol of the KeyKOS print key {(p2,printer)}.

8 - Virtual Console Function - Supported

12 - Pseudo Timer - Supported

10 - Release Pages - Supported

14 - Spool File Manipulation - Not supported

18 - Standard DASD I/O - Supported, although not all the restrictions are checked.

1C - Clear I/O error recording - Gives privileged operation exception

20 - General I/O - Supported

24 - Device type and features - Supported

28 - Channel program modification - Not supported

2C - Return start of Logrec - Gives privileged operation exception

30 - Read page of LOGREC - Gives privileged operation exception

34 - Read system Dump - Gives privileged operation exception

38 - Read system symbol table - Gives privileged operation exception

3C - Update User Directory - Gives privileged operation exception

40 to 48 - Gives privileged operation exception

4C - Generate accounting - Gives privileged operation exception

50 - Save 3705 - Gives privileged operation exception

54 - Control PA2 key - Not supported

58 - 3270 I/O - Supported except for the "line mode write" function which is only supported for clearing the screen

5C - Error message editing - Supported

60 - Virtual storage size - Supported

64 - Named Segment Support - Always gives error code 44, segment not defined

68 - VMCF - Always gives return code 15, paging error

SIO & SIOF - Supported synchronously

TIO - Supported

HIO - Supported

TCH - Supported

STIDP - Supported, values stored do not reflect those from the real machine

STIDC - Supported

SCK - Supported {except doesn't set the clock}

SPKA - Supported

STCTL - Supported

LCTL - Supported, but values are ignored

IPL - Only IPL by device address is supported

SET - Only STORAGE, VIRTUAL, READER, RDR, PRINTER, PRT, PUNCH, PCH, and FILES options are supported

QUERY - Supports same options as SET

DEFINE - Only the STORAGE option is supported

DISPLAY - Supported

STORE - All options except STATUS are supported

BEGIN - Supported

Close - Supported except for 3800 options

SPOOL - Supported except for 3800 options

DISCONN - Supported if a ZMK key is provided when the console is defined with DEFINEDEVICE {(cpsim-definedevice)}

* - Supported

CP - Supported

ORDER - Supported

PURGE - Supported

CHANGE - Supported except for 3800 options

TRANSFER - Supported

LINK {To} disk_name As vaddr2 {mode}

disk_name is resolved in the directory provided to the CP simulator by order code 4 on the definedevice key {(link-dir)} for this simulator. The key may be either to a segment or to a "link object". If a segment it must be already formatted as a normal simulated disk according to CP disk simulation protocol. See LINKF for the source of link objects.

LINK disk_name hhh {As} vaddr2 {mode}
disk_name.hhh, where hhh are hex digits, is resolved in the link directory.