04/17/87: steprates by Delphi, | Category: Delphi - General Information | 2 comments - (Comments are closed)

steprates

26591 17APR87-2224 General Information
steprates
From: TERMITE To: MARTYGOODMAN

Marty,

Can you tell me how to set step rates in RS 1.1. Ram mode of course.

Jim
z

2 comments to steprates

  • pucc_unknown

    26606 18APR87-0049 General Information
    RE: steprates (Re: Msg 26591)
    From: GREGL To: TERMITE

    Termite,

    Read a few messages back as Don Hutchison just dropped the same thing to
    Rick Adams.

    Greg

  • pucc_unknown

    26619 18APR87-0231 General Information
    RE: steprates (Re: Msg 26591)
    From: MARTYGOODMAN To: TERMITE

    At locatins D613, D7C0, and D816 are, respectively,
    the constants for head step in the format routine,
    return head to track zero in the read/write sector
    routine, and the step head in the read/write sector
    routine. These constants will be in vanilla
    Disk 1.1 (step rate set at 30 ms) 53, 3, and 17 (hex)
    respectively. Now, the Last Two Bits of each of those
    numbers in those locations specifies the step rate
    as follows:
    00 = 6 ms step rate
    01 = 12
    10 = 20
    11 = 30

    That is, to set all three constants to reflect a 6 ms step rate,
    set them to 50,00, and 14 (hex) respectively.

    For 12 ms, set them to 51, 1, and 15 respectively (again hex!).

    Hope that helps!

    —marty