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Improved RL01/RL02 disc simulator available

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    Improved RL01/RL02 disc simulator available

    Hello,
    the new Version V 3.04 is now available via my homepage with new features:
    Speed improvement. DPR (Dual Ported Ram ) is now included in QSYS. Result: A memcpy is
    replacing the previously used PIO based controlled I/O. Offline mode will now construct
    Cylinder 0+1 and the bad sector file in memory.
    Of course there are still further improvements possible, like supporting 2 RL drives
    at the same time. I also plan to implement a PCB board with my friend Jonny Jonas ( www.timecontrol.de )
    including also a small display and a faster way to access the SD-Card. Another open point here
    is how to convert the TTL signals in to FPGA world. I used a resistor network and it works fine,
    but it requires absolutely 100% grounding. Alternatively, we could use converter chips like HC4050
    but that does not work for this implementation yet.
    Reinhard

    #2
    Hi All;
    Reinhard, I Thank you for Your efforts, I have already Downloaded What I could of what I see You have available..
    What I am Waiting for is a Board to Convert from RL Drives or any of the Big Washing Machine size drives to SeaGate ST506 MFM Drives.. There is a Hint on Your Web site that You have started to Do that, But, there is not much more than that there.. I do Not have any of the Big Disk Drives, But, I have the UniBus Interface Boards.. And Would love to use those to go to my ST506 Drives, IF possible..
    THANK YOU Marty

    Comment


      #3
      Reinhard,

      What you've done is very impressive. To shift voltages to fpga levels, look at https://www.sparkfun.com/products/11771

      I think that is the type of IC you should use to shift the voltages and be safe.

      Comment


        #4
        Marty,
        The ST506/ST412 MFM-Disc project is in progress but there are other problems.
        It is rather not a technical problem, I lack the necessary information to continue
        in this project. The lack of information is related to the low level disc format.
        Each manufacturer has formated the discs different. E.g. A RQDX-1/2 formated disc
        can't be used with a RQDX-3. and so on ... and so on....
        Regards, Reinhard

        Comment


          #5
          This is an interesting information, thank you !

          Comment


            #6
            Reinhard,

            With respect, I think it might make more sense to finish the ST506 version of your drive emulator first. This should be simpler than the RL series was, there's no need for the line transceivers ICs used for the RL, is there?

            As to the format problem - wouldn't it be possible to emulate the drive on a physical level, and use the original tools to format and initialize it? [I.E. - ZRQxx]

            I realize it's not as sophisticated as your RL solution, but it would be universally compatible then.
            Last edited by RSX11M+; November 17, 2013, 07:57 AM.

            Comment


              #7
              Ok, the ST-506/412 is important for many people but I can not do everything alone.
              My free time is limited and I am not a pensioner (Hope you understand my humor)
              I understand very well the need of a ST-506/412 simulator. The timing is done but I
              have no reference system to find out how the content of headers is implemented.
              I'll give you an update.

              Comment


                #8
                Hi All;
                Reinhard, I Thank You for Your response.. I admire what You have Done and what You have accomplished !!!
                I think when I looked at Your site, there was NO information as far as the ST506 project, so Even If I wanted to build what you have and try and help You, there is not enough information there for the rest of Us to be of any help to You.. I am Sure that there are many people who would have the knowledge and or the expertise to help with this project..
                So, Put out what You have and Maybe someone can help You overcome what ever problems that are present there or at least be able to give You some Ideas..
                THANK YOU marty

                Comment


                  #9
                  Originally posted by PDP11GY View Post
                  Ok, the ST-506/412 is important for many people but I can not do everything alone...
                  What [hardware? software? documentation?] would I need to get for me to be of assistance to your effort?

                  Comment


                    #10
                    I'll open a new thread with questions about ST506/ST412.It would be nice if you can help me.
                    At the moment I can not work continuously because my RD51 is broken. Unfortunately, I lack
                    the necessary information. I only have the Seagate Manuel for the ST506, = RD50. If I have
                    an up and running ST506/ST412 environment again, I will collect the data from one cylinder
                    to use it for reference purpose. Also, one major goal is to implement a "collect" mode. In
                    this case, the FPGA will control the disc and save the whole disc data content to SD-Card.

                    Comment


                      #11
                      Originally posted by PDP11GY View Post
                      Ok, the ST-506/412 is important for many people but I can not do everything alone.
                      My free time is limited and I am not a pensioner (Hope you understand my humor)
                      I understand very well the need of a ST-506/412 simulator. The timing is done but I
                      have no reference system to find out how the content of headers is implemented.
                      I'll give you an update.
                      There are dozens of ST-412 controller implementations documented in disk controller manuals on bitsavers.
                      Try adaptec, cirrusLogic, codata, dec, dsd, dynabyte, emulex, konan. Western Digital and National have detailed
                      descriptions of their chip sets. National app note AN-0413_Disk_Interface_Design_Guide_and_Users_Manual_ Jan86
                      is good. The biggest difference in sector formats is how they deal with error checking, and error correction.

                      cirrusLogic/Practical_Error-Correction_Design_For_Engineers_2ed_1991 has a good discussion on that.

                      you will also run into compensating for write-precompensation in the controller if you work at the bit level on sectors.

                      Comment


                        #12
                        Originally posted by Al Kossow View Post
                        There are dozens of ST-412 controller implementations documented in disk controller manuals on bitsavers.
                        http://bitsavers.org/pdf/adaptec/asi...Controller.pdf
                        http://bitsavers.org/pdf/motorola/_d...view_Oct85.pdf
                        http://bitsavers.org/pdf/sms/asic/OM...ncer_Sep88.pdf
                        http://bitsavers.org/pdf/westernDigital/WD100x/

                        Comment


                          #13
                          Hi All;
                          Here is the link for the National Ap Note..
                          https://ia601607.us.archive.org/22/i...nual_Jan86.pdf
                          THANK YOU Marty

                          Comment


                            #14
                            Originally posted by PDP11GY View Post
                            The timing is done but I
                            have no reference system to find out how the content of headers is implemented.
                            If you are using an RQDX3, the controller uses an SMC 9224. The sector format is described on page
                            617 of http://bitsavers.org/pdf/standardMic...crosystems.pdf

                            The CRC and ECC polynomials are on page 610
                            Last edited by Al Kossow; November 18, 2013, 10:13 AM. Reason: typo

                            Comment


                              #15
                              Originally posted by Al Kossow View Post
                              If you are using an RQDX3, the controller uses an SMC 9224. The sector format is described on page
                              617 of http://bitsavers.org/pdf/standardMic...crosystems.pdf

                              The CRC and ECC polynomials are on page 610
                              The classiccmp thread
                              http://marc.info/?l=classiccmp&m=129644470316554&w=2

                              is also worth looking at for more info on ECC, and some errata on the National app note.

                              Philip is the person who developed the diskferret. It's unfortunate that the hard disk reading firmware for it appears to be stalled.

                              Comment

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