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Amiga 3000/3000T Jumper Settings
    
Jumper  Pins    -01 -02 -03 -04     Function
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J100    4       2-3 2-3 1-2 1-2     Quadrature Clock Phasing
J101    3       2-3 2-3 2-3 2-3     FPU Clock Source
J102    3       2-3 2-3 2-3 2-3     System Clock Source
J103    4       3-4 3-4 3-4 3-4     FPU CS/BERR
J104    3       1-2 1-2 1-2 1-2     CPU Clock Source
J151    3       2-3 2-3 1-2 1-2     ROM Timing
J152    3       2-3 2-3 1-2 1-2     ROM Timing
J180    3       2-3 2-3 2-3 2-3     A2000 ROM Compatibility Jumpers
J181    3       2-3 2-3 2-3 2-3     A2000 ROM Compatibility Jumpers
J200    3       1-2 2-3 1-2 2-3     NTSC/PAL Select
J350    3       1-2 1-2 1-2 1-2     Tick Clock Source
J351    3       2-3 2-3 2-3 2-3     Disable DF1: (1-2 to enable)
J352    3       2-3 2-3 2-3 2-3     Light Pen Source
J481    3       2-3 2-3 2-3 2-3     VDE Scan Double Only Jumper
J482    3       1-2 1-2 1-2 1-2     VDE PLL Loop Adjust
J483    3        -   -   -   -      VDE Factory Test Points
J800    3       1-2 1-2 1-2 1-2     WD33C93
J851    3       1-2 1-2 2-3 2-3     RAM Controller Speed Jumper
J852    5       4-5 4-5 4-5 4-5     -012A Ramsey only (See Notes)
J853    3       2-3 2-3 2-3 2-3     -012A Ramsey only (See Notes)

J852 connecting pins 2 & 3 : 1Mbit, in 256k x 4
J852 connecting pins 1 & 2 : 4Mbit, in 1m x 4


Notes:

    J150, J151:     ROM Timing.
        The ROM timing circuit provides four different speed settings to
        match the output enable and access timing of the system ROMs.

        To set the jumpers, determine the output enable time and access
        times for the ROMs you wish to use.  The ROM must have lower values
        than for the setting you select.

        System standard ROMs have T(oe) = 110ns and T(acc) = 250ns.

        CLK     J151    J150    T(oe)(min.) T(acc)(min.)

        16 MHz   2-3     2-3     157ns       250ns
        16 MHz   2-3     1-2     220ns       312ns
        16 MHz   1-2     2-3     282ns       375ns
        16 MHz   1-2     1-2     345ns       437ns

        25 MHz   2-3     2-3     90ns        160ns
        25 MHz   2-3     1-2     130ns       200ns
        25 MHz   1-2     2-3     170ns       240ns
        25 MHz   1-2     1-2     210ns       280ns

    J180, J181:     ROM Compatibility Jumpers

                            J180    J181

        A2000/A500 ROMS:    1-2     1-2
        A3000 ROMs:         2-3     2-3

    J851-J853:      RAM Controller Compatibility Settings

                                        J852    J853

        -012A Ramsey w/ 256K4 RAMs     4-5     2-3
        Later Ramseys w/ 256K4 RAMs    2-3     1-2
        Later Ramseys w/ 1M4 RAMs      1-2     1-2
    
   

Copyright 2000 Amiga Auckland Inc. All rights reserved.
Revised: August 13, 2005.