Archive-name: ibm-rt-faq/aix-v2/os-hardware/part1
Last-modified: Fri Mar 25 03:14:54 CST 1994
Version: 1.1

Frequently Asked Questions for:  AIX V2.2.1 on IBM RT systems
                                 AIX V2 OS Hardware specific updates.
                                 Part 1 of 1 parts.

The AIX V2 FAQ currently consists of EIGHT parts in 5 topic areas:

     AIX V2 FAQ Index and acknowledgements
     AIX V2 OS Specific hardware issues - one part currently (This FAQ)
     AIX V2 Software questions - in three parts.
     AIX V2 Problem Questions and answers - two parts.
     AIX V2 Porting software notes - in one part currently (more soon).

See the AIX V2 FAQ index posting for a complete index of the AIX FAQ postings.

This FAQ adds additional information to the general hardware FAQ
that is specific to usage by AIX V2.  This section matches the
hardware index numbers and extends that information.

I have included part of the H.1 section here on what is an RT.

 
------------------------------
H.1 - What is an IBM RT?

   More about this RT's history and information may be found in the
   RT hardware FAQ. under this section heading.  A partial summary of
   that entry is included here.

   The IBM RT is a RISC based processor designed by IBM, and unique to
   that platform.  The RT was first announced by IBM in January 1986.
   The processor is generally refered to as 032 processor.  In some
   documentation it is also refered to as the 'ROMP' processor.

   The RT PC Advanced System Processor has a 32-bit Reduced Instruction 
   Set Computer (RISC) architecture developed by IBM and implemented in 
   a 1-micron CMOS technology.  It has sixteen 32-bit general purpose   
   registers and uses 32-bit addresses and data paths. The              
   microprocessor is controlled by 118 simple 2- and 4-byte             
   instructions.  An IBM-developed advanced memory management chip      
   provides virtual memory address translation functions and memory     
   control.  It provides a 40-bit virtual address structure capable of  
   addressing one terabyte of virtual memory. Internal processor
   organization enables the CPU to execute most register-to-register 
   instructions in a single cycle.                 
   The model 115/125 RT PC with their FAST ECC memory, is capable
   of providing the processor with a 32-bit word of data plus ECC each
   100 nsec cycle.  This memory consists of 40 1-megabit IBM RAM chips.     
   These chips are the same megabit technology used in the IBM 3090.    

   For more history, see the Hardware FAQ posted to comp.sys.ibm.pc.rt.

------------------------------
H.7 - What adapter cards are supported in an RT running AIX V2.
 
      The IBM RT has what is called in the industry a ISA bus.  Based on
      the original IBM PC AT bus in design, the RT has 8 I/O slots in the
      tower (6150 model), and 6 slots in the desktop (6151 model).
      Slot 3 and 6 on the tower model and slot 1 on the desktop models are
      eight bit style slots.  Slot 8 on the tower and slot 5 on the desktop
      model are wired slightly different than standard.  See the hardware
      FAQ for more information.
     
      All adapters listed in this section on the hardware FAQ are
      supported by AIX V2.

      Technically, any adapter that conforms to ISA standards would work
      provided there are appropiate device drivers AND no conflicts with
      existing adapters registers and bus addresses.

      The RT diagnostics program disks are unfortunately rather particular
      about OEM cards that attempt to emulate IBM adapters.  This can
      sometimes lead to problems running diagnostics, where the AIX/RT system
      will otherwise run fine under regular operation.  Unknown adapter cards
      usually will be ignored.
 
------------------------------
H.8 - What IBM perhiperials were available?

      All peripherial devices listed in this section on the hardware FAQ are
      supported by AIX V2.

------------------------------
H.14  How do I get a parallel printer attached to an RT?
 
      There are three different ways to attach a centronics parallel
      printer to the RT. The AIX printer driver only supports a maximum
      of two parallel printer interfaces.  The megapel and Mono/Print
      adapters do not have a way of changing the I/O address that they
      answer to, and cannot be used together without disabling the
      printer adapter on the megapel card. To have a second printer is
      supported by using a AT serial/Parallel card, jumpered at the
      secondary printer port address.  If no Mono/Print or megapel 
      adapter is present, then a second Serial/Parallel card can be used.

 1) AT Serial/Parallel interface card.
    Parallel port primary address = 3BC
    Parallel port secondary address = 278

 2) PC/XT Monochrome/Parallel printer card.
    Parallel port only address = 3BC 
    No jumper available to disable this port.

 3) Megapel card has a parallel interface on it. 
    Parallel port only address = 3BC
    Swich 1 position 2 enables/disables the port.
    Shipped disabled from factory.

      WARNING: Some combinations of interface cards can cause
      I/O channel conflicts.  Both Serial/Parallel interface cards
      CAN be present with either a Mono/Print or Megapel adapter,
      IF the parallel port on one of the S/P adapters is not defined
      with the devices command.

      Readers of this newsgroup have reported success with clone 
      parallel printer cards operating correctly.  I suspect that the
      diagnostics diskettes MAY have problems with them however.

------------------------------
H.16 - AT Co-Processor information.

      The IBM PC AT Math Coprocessor, Feature code #4756, provides for
      execution of many IBM PC and IBM PC AT programs concurrent with and
      under control of the RT main processor. With appropriate program
      support (the RT PC AT Coprocessor Services licensed program, (5669-057)
      (Feature #5030), the option enables the RT to emulate the IBM PC AT
      Models 068 and 099. Application execution is concurrent with RT program
      execution. 

      Note: The megapel display adapter is not usable as a console or for
      application output for the PC AT coprocessor.

------------------------------
H.17 - How can I get the maximum data on a 6157 tape drive?

   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==
   Submitter: crow@austin.ibm.com (David L. Crow)
              IBM Advanced Workstations Division
   Date: 30 Apr 92 14:12:59 GMT

  >We have the 6157-002 model (150Meg, I think) and for some
  >reason, it needs three tapes to backup only 240Meg of data.

    DC 600A tapes should hold 118 MB of data.  Of course this is somewhat
  dependent on the RT systems ability to keep the data moving to the tape
  as it is streaming.  If there is a break in data bacause the backup command
  can't get it there quick enough, then you'll lose some of your capacity.
  Here is an item from ASKQ two or three years ago that describes what
  flags to use to make sure that you get the maximum capacity out of your
  6157.  This probably could go into the FAQ (except the FAQ is pretty
  much just for AIX Version 3).

  ============================================
  Subject: 6157 TAPE INFORMATION FOR AIX BACKUP COMMAND

  The correct descriptions for the -s and -d flags of the AIX backup
  command are:

   -slength

      Specifies the length of the usable space on a tape medium. This is a
      combination of the physical length and the number of tracks on the
      tape. The default "length" is 2700.

      To get the value for "length", you should multiply the physical
      length of the tape by the number of tracks (see table below).

  -ddensity

      Specifies the amount of data a system can write to a tape medium in
      bytes per inch. The default "density" is 700 bytes per inch.

      The density written to the tape is hardware controlled and can not
      be changed. The 6157-001 writes at 10,000 ftpi (flux transactions
      per inch) which is approximately equivalent to a density rating of
      8,000 bits per inch. The 6157-002 writes at 12,500 ftpi which is
      equivalent to a density rating of 10,000 bits per inch.

      The -d (density) parameter is used with 0.5 inch tape drives to
      specify the density, such as 800, 1600, or 6250 bpi, but doesn't
      affect the density, that is, bits per inch, of the 6157.

      The -d parameter is used for the 6157 in the calculation of what
      quantity of data will be put on the tape. To increase the amount of
      data on the tape, the value for -d should be 1000 for 6157-001 or
      1200 for 6157-002.

  Reference: AIX/RT Commands Reference Volume 1, SC23-2011-1, page 91.
             AIX PS/2 Commands Reference, SC23-2025, page 35.

  CALCULATION OF TAPE CAPACITY:

      The following formula yields the approximate capacity of a tape:

      # tracks * length * 11 inches * density = capacity (in bytes).

       9 * 300 * 11 * 1000 =  29,700,000 bytes or about 29 MB
      18 * 600 * 11 * 1200 = 142,560,000 bytes or about 142 MB

      The "11 inches" is the length of the recording foot, the actual
      amount of data stored on the tape per foot, and the interblock gaps
      take up approximately 1 inch per foot.

  TABLE:

  For the following AIX command(s), the values for -s and -d are in the
  table below:

       find ./ -print | backup -iv -C2000 -f/dev/rmt0 -sXXXX -dYYYY

   Recommendations for 6157-001:

   TAPE CARTRIDGE LENGTH    TRACKS   -s    -d   CAPACITY

   3M DC 300A     300 feet     9    2700  1000    29 MB
   3M DC 300XLP   450 feet     9    4050  1000    44 MB
   3M DC 600A     600 feet     9    5400  1000    59 MB

   Recommendations for 6157-002:

   TAPE CARTRIDGE LENGTH    TRACKS   -s    -d   CAPACITY

   3M DC 600A     600 feet    15    9000  1200   118 MB
   3M DC 600XTD   600 feet    18   10800  1200   142 MB
   ==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==**==

------------------------------
H.18 - What hard disks can be used in an RT with AIX V2?

     At this time the hardware FAQ lists all known drives supported
     by IBM with an RT running AIX.

     To use a NON-IBM ESDI drive on an RT, it will have to be very
     close in its geometry to one of the IBM supported drives.
     I have not yet tried to use ESDI drives with larger than 310 Mbytes
     of space with AIX.  For larger SCSI drives, see section H.21.
       
     See the topics on AIX usage of ESDI disks covered in more detail in
     sections Q.11 thru Q.13.

------------------------------
H.21 - What SCSI devices can be attached?

     The regular IBM suported SCSI adapter is slightly different from most
     workstation adapters.  IBM chose to implement their adapter with the
     'Differential Driver/Receiver option' and with the 'Alternative 2
     connector' as per the proposed ANSI standard SCSI-1.  The SCSI
     interface conforms to (then) proposed ANSI standard X3T9.2/82-2
     Revsion 17B.  

     Two wires are used for each signal lead in a push-pull signaling
     method also called 'differential-ended'.  What this boils down to
     is that the IBM SCSI card is electriclly incompatible with a lot
     of the off-the-shelf SCSI drives.  Most drives for other workstations
     and PC's use a 'single-ended' SCSI implementation.
     
     Now that SUN and IBM have announced differential interface adapters
     for thier workstations, we may see more disk drives available with
     native differential interfaces.

     IBM officially supported only one device attached to the SCSI
     interface card, the IBM 9332 'Athens' disk drive.

     Due to a design problem in the minidisk driver code for the IBM SCSI
     adapter, SCSI disks over 1 Gig will not work.  Worse, the address
     for the sector will wrap back to zero, completely destroying the
     minidisk partition table, and the first filesystem on the drive.

     See question topic Q.14 for information on adding NON-IBM SCSI disks
     to an AIX system.

------------------------------
H.22 - What do the LED codes mean during power on.

       The initial IPL sequence of LED codes are listed in the hardware FAQ.
       After LED code 22 and 26 is displayed control is passed to the
       loadable VRM boot code.  As VRM is booting, these LED codes are 
       displayed by Loadable Power On Self Test routines (LPOST).

 LPOST LED values during IPL
 30 Monochrome display adpater.
 31 Color graphics adapter (EGA).
 32 6153 display adapter.
 33 6154 display adapter.
 34 6155 display adapter.
 35 Fixed disk in location C.
 36 Advanced processor card.
 39 Diskette in location A.
 40 Diskette in location B.
 43 PC AT Coprocessor option.
 44 Floating-Point accelerator.
 45 Monochrome display/Printer adapter.
 46 3278/79 emulation adapter.
 47 Memory card in slot C bad - 4Meg enhanced card.
 48 Memory card in slot D bad - 4Meg enhanced card.
 49 RS-232C 8-port adapter.
 50 PC Network adapter.
 51 Serial device - serial/parallel adapter.
 52 SCSI adapter.
 53 RS-232C 4-port adapter 1
 54 Parallel device - serial/parallel adapter.
 55 RS-232C 4-port adapter 2.
 56 RS-422A 4-port adapter 1.
 57 RS-422A 4-port adapter 2.
 58 5080 attachment adapter.
 59 S/370 attachment adapter.
 5U Memory expansion option or Enhanced Advanced processor and
  Memory Mgmt. card.
 60 Multiprotocol communications adapter.
 61 5080 peripheral adapter.
 62 Baseband adapter.
 63 Lighted PF keys.
 64 Dials.
 65 5081 display adapter 1.
 66 5081 display adapter 2.
 67 Advanced floating-point accelerator.
 68 Floating-poing processor on Advanced Processor and 
  Memory Mgmt. card.
 69 Memory option on Advanced processor and Memory Mgmt. card.
 71 Memory card in slot C bad - 2 Mb card.
 72 Memory card in slot C bad - 1 Mb card.
 73 Memory card in slot C bad - 4 Mb card.
 74 Memory card in slot C bad - 8 Mb enhanced card.
 76 Memory card in slot D bad - 1 Mb card.
 77 Memory card in slot D bad - 2 Mb card.
 78 Memory card in slot D bad - 4 Mb card.
 79 Memory card in slot D bad - 8 Mb enhanced card.
 80 Mouse device.
 81 keyboard device.
 82 Speaker device.
 84 Bus memory cards.
 85 Tablet device.
 86 Token ring network adapter.
 87 RS-422A 8-port adapter.
 88 Reserved (Power on).
 90 Streaming tape adapter.
 93 Diskette read/write error.
 94 Final LPOST found no display - Fatal.
 95 Fixed-disk write error.
 9c MIL-STD 188 8-port adapter.
 cc 6156 portable disk drive model 3.
 cu 6156 portable disk drive model 1.
 uc 6192 expander card.
 uu 6192 receiver card.
 
------------------------------
H.23 - What does LED code xx mean (during AIX runtime)?

 All the LED codes are summarized in a little pamplet from IBM
 manual number SC23-2022 "RT PC VRM/Hardware Quick Reference".
 The maroon colored binder "IBM RT PC Problem Determination Guide"
        contains two manuals: 
           "IBM RT PC Problem Determination Guide" number SA23-2604 
           "IBM RT AIX Operating System Problem Determination Guide" 
              number SA23-2603

        Procedures a given for a variety of LED codes, what to check, 
        and how to take system dumps, reading the error logs and more.
        Recovery procedures are also given for some error codes.

 VRM LED Values during runtime.
 c0 VRM dump complete
 c4 VRM dump abend.
 c5 The diskette is damaged, insert another in drive A.
 c6 VRM dump waiting for diskette to be inserted.
  the 'c6' will alternate on the LEDs with the VRM
  abend code.  After the diskette has been inserted,
  a keyboard sequence is used to start the dump.
 c7 The dump diskette is full, insert next dump diskette.
 c8 The system is checking the diskette for damage.
 c9 VRM dump writing to diskette.

 VRM Abend [Abnormal End] codes (alternate with the 'C6' code above)
 01 A level-2 hardware interrupt has occured.
 02 A machine check has occured.
 03 The VRM received an SVC that was not issued by a
  virtual machine.
 04 An unidentified program check occured.
 05 A trap instruction was encountered.
 06 A data protection exception has occured.
 07 An unidentified IAR exception has occured.
 08 An unidentified IAR exception has occured.
 09 An IAR protection exception has occured.
 10 A privileged operation exception has occured.
 11 An illegal operatin exception has occured.
 12 A page fault occured before VRM was fully operational.
 13 A page fault occured that could not be processed by VRM.
 14 A floating-point exception has occured.
 15 The VRM encountered an unresolved reference.
 16 The VRM has encountered a stack overflow.
 17 All paging space is in use.
 18 The VRM tried to reference an address that is not valid.
 19 The VRM encountered a permanent I/O error in the paging area.
 20 The VRM does not have enough real memory to continue.
 21 The minidisk cannot be accessed.
 22 The VRM cannot find the paging space minidisk.
 23 The VRM has received an initialization data that is not valid.
 24 The VRM is unable to allocate a system control block.
 25 The VRM could not find a disk device driver.
 26 An I/O channel error has occured.
 27 An I/O error occured while accessing cylinder 0 of a fixed disk.
 28 A processor I/O error has occured.
 29 A floating-point DMA error has occured.

 Flashing LED values during VRM system initialization:
 02 Read error - fatal.
 03 Insuffient memory to load module - fatal. 
 04 Insuffient memory for the DDA  - fatal. 
 05 Insuffient memory for the MIT  - fatal. 
 06 Insuffient memory for the DTOC - fatal. 
 07 Insuffient memory for the match list - fatal.
 08 Relocation symbol type not supported.
 09 File type not supported.
 10 Invalid device - fatal.
 11 Invalid index for address from inode - fatal.
 12 Inode out of range - fatal.
 13 Address out of range - fatal.
 14 File not found - fatal.
 15 No freeblock header space - fatal.
 16 Freeing freespace - fatal.
 17 Address already allocated - fatal.
 18 Not on a word boundry - fatal.
 19 Invalid file name - fatal.
 20 Inavlid IOCN in the file name.
 21 Invalid IOCN in the DDS.
 22 Invalid length field in the DDS.
 23 Execution of loaded program failed.
 24 No entry point was found.
 25 Bad load module.
 45 Base device missing at VRM install time.
 46 Probable programming error (contact IBM).
 47 Error in vtcp command.
 48 Define code SVC failed for vtcp module.
 49 Insufficient memory for segment to read code.
 50 Define Device SVC failed for control program.
 51 Attach device SVC failed for control program.
 52 Define Device SVC failed for a new device.
 53 Define Device SVC failed for the VTRM.
 54 VTRM could not be installed.
 99 Unexpected program or machine check - fatal.
 
------------------------------
H.26 - Serial port cards maximums and limitations.

      Under AIX/RT the maximum rate supported by the various serial cards
      is 19,200 baud.  If you have one of the very old unbuffered 4-port
      cards, you may experience a great deal of overrun problems at high
      speeds, (>4800 baud) plus system loading during communication.

================================================================================
             *** FAQ Continued in AIX Software issues Part 1 ***
================= end of ibm-rt-faq/aix-v2/os-hardware/part1 ===================
-- 

Posted around the first of each month to comp.sys.ibm.pc.rt, and
to comp.unix.aix.

This FAQ is dedicated to use of the AIX Version 2 operating system, running
on the IBM RISC processor known as the RT.  The RT is known also as 
an IBM model 6150 or 6151 machine.

For AIX RT  submissions E-mail to:   aix-rt@antimatr.hou.tx.us
For AOS RT  submissions E-mail to:   aos-rt@antimatr.hou.tx.us
For MACH RT submissions E-mail to:   mach-rt@antimatr.hou.tx.us
For general Q&A submissions (hardware and other stuff) E-mail to:
   faq-rt@antimatr.hou.tx.us

Other comments and correctons should be sent to the author:
    Mark Whetzel
    DOMAIN addr: markw@antimatr.hou.tx.us
    BANG address:  ..!uhnix1!lobster!antimatr!markw
    Daytime work number  8AM-5PM M-F CST  VOICE: (713) 963-2544

--
AIX..... NOT just another UNIX. (tm)
Mark Whetzel                          | My own RT system.. My own thoughts..
DOMAIN: markw@antimatr.hou.tx.us      | IBM RT/135 running AIX 2.2.1 
UUCP ..!menudo!lobster!antimatr!markw | comp.sys.ibm.pc.rt FAQ maintainer.
