S3/system3.txt

   1     The IBM System/3 simulator is configured as follows:
   2
   3         CPU     5410 (Model 10) CPU with 64KB of memory.
   4         PKB     5471 Printer/Keyboard console.
   5         CDR     1442 Card Reader
   6         CDP     1442 Card Punch
   7         CDP2    1442 2nd stacker
   8         LPT     1403 Line Printer
   9         R1      5444 Top Drive (removeable)
  10         F1      5444 Top Drive (fixed)
  11         R2      5444 Bottom Drive (removeable)
  12         F2      5444 Bottom Drive (fixed
  13
  14     The only CPU options are to set Model 15 mode (not implemented), DPF
  15 (Dual Programming Facility, not implemented), and the memory size 8K, 16K,
  16 32K, 48K, or 64K.
  17
  18     CPU registers are the standard System/3 set:
  19
  20         name            size    Description
  21
  22         IAR-P1          16      Instruction Address Register for Program Level 1
  23         ARR-P2          16      Address Recall Register for Program Level 1
  24         IAR-P2          16      IAR for Program Level 2 (not implemented)
  25         ARR-P2          16      ARR for Program Level 2 (not implemented)
  26         AAR             16      A-Address Register
  27         BAR             16      B-Address Register
  28         PSR             16      Program Status Register
  29         XR1             16      Index Register 1
  30         XR2             16      Index Register 2
  31         IAR<0:7>        16      IAR for interrupt level 0 thru 7
  32         ARR<0:7>        16      ARR for interrupt level 0 thru 7
  33
  34         Plus these simulator registers:
  35
  36         IAR             16      Value of last IAR used.
  37         LEVEL            8      Current operating level (8=P1, 9=P2,
  38                                         0 thru 7 = Interrupt level)
  39         SR              16      Front Panel switches
  40         INT             16      Interrupt Request Flags
  41         WRU             8       Simulator Interrupt Character
  42         BREAK           17      Breakpoint Address
  43         DEBUG           16      Debugging bits:
  44                                 0x01: Write all instructions executed to
  45                                         file trace.log.
  46                                 0x02: Write details of all Disk I/O
  47                                         requests to trace.log.
  48                                 0x80: Breakpoint on first character
  49                                         written to 5471 printer.
  50
  51 1       5471 Printer/Keyboard
  52
  53         This is the operator console.  It has the following registers:
  54
  55         FLAG    5471 Flag Bytes
  56         IBUF:   Input character from keyboard
  57         OBUF:   Output character to printer
  58         POS:    Number of characters printed
  59         TIME:   Delay for device operation
  60         REQKEY: ASCII value of key mapped to 5471 REQUEST key
  61         RTNKEY: ASCII value of key mapped to 5471 RETURN key
  62         ENDKEY: ASCII value of key mapped to 5471 END key
  63         CANKEY: ASCII value of key mapped to 5471 CANCEL key
  64
  65
  66 2       1442 Card Reader.  This reader reads 80-column cards; the input
  67         is usually an ASCII file which is translated to EBCDIC when read,
  68         but optionally can be a binary file in EBCDIC format (such as an
  69         object program).
  70
  71         LAST    Last card switch
  72         ERR     Card Reader Error
  73         NOTRDY  1442 reader not ready (not attached or past EOF)
  74         DAR     Data Address Register (shared with punch)
  75         LCR     Length Count Register (shared with punch)
  76         EBCDIC  EBCDIC mode flag: if 1, input is 80-col EBCDIC binary.
  77                 (IPL from 1442 automatically sets this to 1).
  78         S2      Stacker 2 is selected when this is 1
  79         POS     Number of cards read
  80         TIME    Device Delay
  81
  82         The real hardware 1442 had only 1 hopper for cards, whether
  83         these were used for blank cards for punching, or cards to be
  84         read.  Cards could be read without a feed cycle, then
  85         punched.  When punching cards, the SCP does a read of a card,
  86         makes sure it is blank, and then punches it.  To simulate
  87         this without requiring that a stack of blank lines be attached
  88         to the card reader device, a special feature of the simulator
  89         is this:  if no file is attached to the cdr device, but a file
  90         is attached to the cdp or the cdp2 devices, any read from the
  91         reader will return a blank card -- i.e. when punching, an
  92         unattached cdr device is assumed to be loaded with an unlimited
  93         supply of blank cards.
  94
  95
  96 3       1442 Card Punch.  Normally cards are written to the attached
  97         disk file as ASCII with newline/cr delimiters.  But an optional
  98         flag allows writing as 80-column binary EBCDIC.
  99
 100         ERR     Card Punch Error
 101         EBCDIC  When this is 1, output will be 80-col EBCDIC.
 102         S2      When this is 1, output is placed in stacker 2
 103         NOTRDY  1442 punch not ready (not attached)
 104         DAR     Data Address Register (shared with reader)
 105         LCR     Length Count Register (shared with reader)
 106         POS     Number of cards punched
 107         TIME    Device Delay
 108
 109 4       1442 Stacker 2.  When cards are to be punched in stacker 2,
 110         attach a disk file to this device (cdp2) to hold that output.
 111         Note: When SCP punches cards, the default is to punch in
 112         stacker 2.
 113
 114         POS0    Number of cards punched.
 115
 116 5       1403 Printer.  This is a 132-column output device, emulating
 117         the famous IBM 1403, models 2, 6, and N1.  Output is always
 118         translated to ASCII with newline/CR delimiters.  Page advance
 119         is output as a form feed.
 120
 121         ERR     1403 error flags
 122         LPDAR   Data Address Register
 123         LPFLR   Forms Length Register
 124         LPIAR   Image Address Register
 125         LINECT  Current Line on form
 126         POS     Number of lines printed
 127
 128 6       5444 Disk Drives (R1, R2, F1, F2)
 129
 130         The 5444 came as a set of two drives, each with two disks.  The
 131         top disk in a drive was removable, the bottom fixed.  The first
 132         drive consists of disks R1 and F1, the second drive R2 and F2.
 133         Each disk holds 2,467,600 bytes of user data, plus 3 alternate
 134         tracks and a CE track.  Flagging of alternate tracks is not
 135         supported in this version of the simulator.
 136
 137         NOTRDY  Drive not ready (not attached)
 138         SEEK    Drive is busy with a seek operation
 139         DAR     Data Address Register
 140         CAR     Control Address Register
 141         ERR     Error Flags (16 bits)
 142         CYL     Current Cylinder (0 thru 203)
 143         HEAD    Current head (0 or 1)
 144         POS     Current position in attached disk file
 145         TIME    Device Delay
 146
 147 7       Symbolic Display and Input
 148
 149         The System/3 Simulator supports symbolic display and input.
 150         Display is controlled by command line switches:
 151
 152         (none)  display as hex EBCDIC
 153         -c      display bytes as characters
 154         -m      display instruction mnemonics.
 155         -a      display a 256-byte block of memory in both hex and ASCII.
 156
 157         The symbolic  format contains the same elements as the machine
 158         language operation, but not always in the same order.  The
 159         operation code frequently specifies both the opcode and the Q byte,
 160         and the top nybble of the opcode is determined by the format of the
 161         addresses.
 162
 163         Addresses take two forms:  the direct address in hex, or a relative
 164         address specified thusly: (byte,XRx) where 'byte' is a 1-byte
 165         offset, and XRx is either XR1 or XR2 for the two index registers.
 166         Use these formats when 'address' is indicated below:
 167
 168         When 'reg' is mentioned, a mnemonic may be used for the register,
 169         thusly:
 170
 171         IAR     Instruction Address Register for the current program level
 172         ARR     Address Recall Register for the current program level
 173         P1IAR   IAR for Program Level 1
 174         P2IAR   IAR for Program Level 2
 175         PSR     Program Status Register
 176         XR1     Index Register 1
 177         XR2     Index Register 2
 178         IARx    IAR for the interrupt level x (x = 0 thru 7)
 179
 180         All other operands mentioned below are single-byte hex, except for
 181         the length (len) operand of the two-address instructions, which is a
 182         decimal length in the range 1-256.
 183
 184         In operations where there is a source and a destination, the
 185         destination is always operand 1, the source is operand 2.
 186
 187         No-address formats:
 188         ------------------
 189
 190         HPL hex,hex             Halt Program Level, the operands are the
 191                                 Q and R bytes.
 192
 193
 194         One-address formats:
 195         -------------------
 196
 197         A reg,address           Add to register
 198         CLI address,byte        Compare Logical Immediate
 199         MVI address,byte        Move Immediate
 200         TBF address,mask        Test Bits Off
 201         TBN address,mask        Test Bits On
 202         SBF address,mask        Set Bits Off
 203         SBN address,mask        Set Bits On
 204         ST reg,address          Store Register
 205         L reg,address           Load Register
 206         LA reg,address          Load Address (reg can only be XR1 or XR2)
 207         JC address,cond         Jump on Condition
 208         BC address,cond         Branch on Condition
 209
 210         These operations do not specify a qbyte, it is implicit in the
 211         opcode:
 212
 213         B address               Unconditional branch to address
 214         BE address              Branch Equal
 215         BNE address             Branch Not Equal
 216         BH address              Branch High
 217         BNH address             Branch Not High
 218         BL address              Branch Low
 219         BNL address             Branch Not Low
 220         BT address              Branch True
 221         BF address              Branch False
 222         BP address              Branch Plus
 223         BM address              Branch Minus
 224         BNP address             Branch Not Plus
 225         BNM address             Branch Not Minus
 226         BZ address              Branch Zero
 227         BNZ address             Branch Not Zero
 228         BOZ address             Branch Overflow Zoned
 229         BOL address             Branch Overflow Logical
 230         BNOZ address            Branch No Overflow Zoned
 231         BNOL address            Branch No Overflow Logical
 232         NOPB address            No - never branch
 233
 234         (substitute J for B above for a set of Jumps -- 1-byte operand (not
 235         2), always jumps forward up to 255 bytes from the address following
 236         the Jump instruction. In this case, 'address' cannot be less than
 237         the current address, nor greater than the current address + 255)
 238
 239         Two-address formats (first address is destination, len is decimal 1-256):
 240         -------------------
 241
 242         MVC address,address,len         Move Characters
 243         CLC address,address,len         Compare Logical Characters
 244         ALC address,address,len         Add Logical Characters
 245         SLC address,address,len         Subtract Logical Characters
 246         ED address,address,len          Edit
 247         ITC address,address,len         Insert and Test Characters
 248         AZ address,address,len          Add Zoned Decimal
 249         SZ address,address,len          Subtract Zoned Decimal
 250
 251         MNN address,address             Move Numeric to Numeric
 252         MNZ address,address             Move Numeric to Zone
 253         MZZ address,address             Move Zone to Zone
 254         MZN address,address             Move Zone to Numeric
 255
 256         I/O Format
 257         ----------
 258
 259         In the I/O format, there are always 3 fields:
 260
 261         da - Device Address 0-15 (decimal)
 262         m - Modifier 0-1
 263         n - Function 0-7
 264
 265         The meaning of these is entirely defined by the device addressed.
 266
 267         There may be an optional control byte, or an optional address (based
 268         on the type of instruction).
 269
 270         SNS da,m,n,address              Sense I/O
 271         LIO da,m,n,address              Load I/O
 272         TIO da,m,n,address              Test I/O
 273
 274         SIO da,m,n,cc                   Start I/O -- cc is a control byte
 275
 276         APL da,m,n                      Advance Program Level
 277
 278
 279 8       Device Programming.
 280
 281         Note: On a model 15, interrupts are used for all devices.  On
 282         other models, interrupts are only used for the printer/keyboard.
 283
 284         This is a summary of the DA, M, N, and CC codes for all supported
 285         devices:
 286
 287         5471 Printer Keyboard
 288         ---------------------
 289
 290                 The PKB has 2 visible indicators: Proceed and Request
 291                 Pending.  It has a normal keyboard and 4 special keys:
 292                 Request, Return, End, and Cancel.
 293
 294                 SIO 1,0,0,XX    Start Keyboard Operation, bit masks for XX are:
 295                                 X'20': Request Pending Indicator On
 296                                 X'10': Proceed Indicator On
 297                                 X'04': Request Key Interrupts Enable (1) Disable (0)
 298                                 X'02': Other Key Interrupts Enable (1) Disable (0)
 299                                 X'01': Reset request key and other key interrupts
 300
 301                 SIO 1,1,0,XX    Start Printer Operation, bit masks for XX are:
 302                                 X'80': Start Printing
 303                                 X'40': Start Carrier Return
 304                                 X'04': Printer Interrupt Enable(1) or Disable (0)
 305                                 X'01': Reset Printer Interrupt
 306
 307                 LIO 1,1,0,addr  Load Printer Output Character
 308                                 addr is address of low-order (highest numbered)
 309                                 byte of two-byte field, and high-order byte
 310                                 (that is, addr - 1) is loaded into output
 311                                 register to print.  Printing is done one character
 312                                 at a time.
 313
 314                 SNS 1,0,1,addr  Sense Status Bytes 0 and 1:
 315                                 Byte 0 (leftmost) is the character typed in
 316                                         in EBCDIC.
 317                                 Byte 1 is status:
 318                                 X'80': Request key interrupt pending
 319                                 X'40': End or Cancel key interrupt pending
 320                                 X'20': Cancel key pressed
 321                                 X'10': End Key Pressed
 322                                 X'08': Return or data key interrupt pending
 323                                 X'04': Return key pressed
 324
 325                 SNS 1,0,3,addr  Sense Status Bytes 2 and 3: returns 0000 in
 326                                         this sim.
 327
 328         1442 Reader/Punch
 329         -----------------
 330
 331                 SIO 5,0,0,XX    Feed Card without reading/punching
 332                                 XX is stacker select for all functions: 0 = stacker
 333                                 1 (normal), 1 = stacker 2.
 334
 335                 SIO 5,0,1,XX    Read Card
 336                 SIO 5,0,2,XX    Punch and Feed
 337                 SIO 5,0,3,XX    Read Column Binary
 338                 SIO 5,0,4,XX    Punch with no feed
 339
 340                 TIO 5,0,0,addr  Branch to addr if not ready or busy
 341                 TIO 5,0,2,addr  Branch to addr if busy
 342                 TIO 5,0,5,addr  (mod 15 only) branch if interrupt pending
 343
 344                 APL 5,0,0       Loop (or switch prog levels) if not ready/busy
 345                 APL 5,0,2       Loop (or switch) if busy
 346                 APL 5,0,5       Loop (or switch) if interrupt pending (mod 15 only)
 347
 348                 LIO 5,0,0,addr  Load 2-byte field to Length Count Register
 349                 LIO 5,0,4,addr  Load 2-byte field to Data Address Register
 350                                 (DAR is incremented by a read/punch operation and must
 351                                 be reset every card)
 352
 353                 SNS 5,0,1,addr  Sense CE indicators (0000 returned in this sim)
 354                 SNS 5,0,2,addr  Sense CE indicators (0000 returned in this sim)
 355                 SNS 5,0,3,addr  Sense Status Indicators: (only simulated bits shown)
 356                                 X'8000': Read Check
 357                                 X'4000': Last Card
 358                                 X'2000': Punch Check
 359                                 X'1000': Data Overrun
 360                                 X'0800': Not Ready
 361
 362
 363         1403 Printer
 364         ------------
 365
 366                 SIO 14,0,0,XX   Line space XX lines (0-3 valid in XX)
 367                 SIO 14,0,2,XX   Print a line space (0-3 valid in XX)
 368                 SIO 14,0,4,XX   Skip Only (line number 1-112 in XX)
 369
 370                 SIO 14,0,6,XX   Print and Skip (line number 0-112 in XX)
 371
 372                 TIO 14,0,0,addr Branch to addr if not ready
 373                 TIO 14,0,2,addr Branch to addr if buffer busy
 374                 TIO 14,0,3,addr Branch to addr if interrupt pending (mod 15 only)
 375                 TIO 14,0,4,addr Branch if carriage busy
 376                 TIO 14,0,6,addr Branch if printer busy
 377
 378                 APL 14,0,0      Loop (or switch prog levels) if not ready/check
 379                 APL 14,0,2      Loop (or switch) if buffer busy
 380                 APL 14,0,3      Loop (or switch) if interrupt pending (mod 15 only)
 381                 APL 14,0,4      Loop (or switch) if carriage busy
 382                 APL 14,0,6      Loop (or switch) if printer busy
 383
 384                 LIO 14,0,0,addr Load 1 byte to Forms Length Reg at addr-1
 385                 LIO 14,0,4,addr Load 2 bytes to Chain Image Address Register
 386                 LIO 14,0,6,addr Load 2 bytes to Data Address Register
 387
 388                 SNS 14,0,0,addr Sense Character Count
 389                 SNS 14,0,4,addr Sense LPIAR (Image Address Register)
 390                 SNS 14,0,6,addr Sense LPDAR (data addres register)
 391
 392
 393         5444 Disk Drives
 394         ----------------
 395
 396                 Each drive has two disks (upper and lower), each disk
 397                 has two surfaces (upper and lower), each surface has
 398                 24 256-byte sectors, sectors are number 0 thru 23 on
 399                 upper surface, 32 thru 55 on lower.
 400
 401                 d = drive, 0 is R1/F1, 1 is R2/F2
 402                 s = surface, 0 = upper (removable), 1 = lower (fixed)
 403
 404                 The Control register points to the leftmost byte of a 4-byte
 405                 control field in memory with these bytes:
 406
 407                         F - Flag byte (not supported in this sim)
 408                         C - Cylinder Address (0-203)
 409                         S - Sector Number (0-23, or 32-55) in top 6 bits
 410                         N - Number of sectors minus 1
 411
 412                 These have meaning for all operations except seek, seek uses
 413                 the fields differently.
 414
 415                 SIO 1d,s,0,XX   Seek, XX not used, control field is used:
 416
 417                         F - not used
 418                         C - not used
 419                         S - high bit is head to be used 0-upper 1-lower
 420                             low bit is direction to move 0-back 1-forward
 421                         N - number of cylinders to move
 422
 423                 SIO 1d,s,1,XX   Read, values of XX are as follows:
 424                         X'00':  Read Data
 425                         X'01':  Read Identifier (updates control field, no
 426                                         data is read)
 427                         X'02':  Read Data Diagnostic
 428                         X'03':  Verify (does not read, but checks)
 429
 430                 SIO 1d,s,2,XX   Write, values of XX are as follows:
 431                         X'00':  Write Data
 432                         X'01':  Write Identifier (24 sectors with byte at
 433                                         data address register)
 434
 435                 SIO 1d,s,3,XX   Scan. All 256 bytes in memory at data
 436                                 address register are compared to disk
 437                                 sectors on current track, except those
 438                                 bytes of X'FF' are not compared.  Values of
 439                                 XX are:
 440
 441                                 X'00': Scan Equal
 442                                 X'01': Scan Low or Equal
 443                                 X'02': Scan High or Equal
 444
 445                 LIO 1d,0,4,addr Load Data Address Register
 446                 LIO 1d,0,6,addr Load Disk Control Address Register
 447
 448                 TIO 1d,0,0,addr Branch if not ready/unit check
 449                 TIO 1d,0,2,addr Branch if busy
 450                 TIO 1d,0,4,addr Branch if Scan Found
 451
 452                 APL 1d,0,0      Loop if not ready/unit check
 453                 APL 1d,0,2      Loop if busy
 454                 APL 1d,0,4      Loop if scan found
 455
 456                 SNS 1d,0,2,addr Sense Status Bytes 0 and 1: (simulated
 457                                 bits only are shown, otehrs are 0):
 458                                 X'1000': equipment check
 459                                 X'0800': data check
 460                                 X'0400': No record found
 461                                 X'0100': Seek Check (past cyl 203)
 462                                 X'0080': Scan equal Hit
 463                                 X'0040': Cylinder 0
 464                                 X'0020': End of Cylinder
 465                                 X'0010': Seek Busy
 466                 SNS 1d,0,3,addr Sense bytes 2 and 3 (0000 in this sim)
 467                 SNS 1d,0,4,addr Sense Data Address Register
 468                 SNS 1d,0,6,addr Sense Control Address Register
 469
 470
 471
 472