Page 697 - Engineering Digital Design
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P-terms
 FIGURE 13.44
                                    A-MAXDLY
                            C
        BC
                    A-GO
                        C-CNT-GO
                B-CNT
            B • HALT
 ABC
                                B
 AC
  ABC • MXDLY
    BC-CNTHALT
 BC-GO
 BC-CNT
 ABC • MNDLY • HOLD
 ABC • MXDLY • HOLD
 ABC
 ABC
 ABC
                                        »8
                    0
                                             A
                -
                                -
    -
                        -
 -
        -
                            -
 0
                                    1
            -
 -
 1
 1
 1
 1
 1
 1
 1
                                       '7
                            -
                    -
                        -
                                             B
                                    -
 0
 0
 0
 -
 0
 0
                                1
        1
 0
                1
 1
            1
    1
 1
 1
         "I
 •1
                                        'a
    0
                             1
                                             C
                                -
 0
 1
 1
 0
 1
 0
 0
 1
                        1
 1
         _
                                        's
                        -
    -
 _
 -
 -
 0
                                -
                                    0
         _
 -
 -
                        -
    -
 _
                             _
 -
                                -
                                        >4
 _
 _
 0
 0
 _
                                        I,
         _
                                -
                                    -
                o
 -
                             _
 Q
 _
 -
 _
 -
 _
                                                    PLA Inputs
                        1
    1
                                             MNDLY* MXDLY* CNT
         _
    -
                                        '2
                    1
                        1
 1
                                             GO
 ^_
         _
            o
                                        "1
    0
 ** Indicates an active low output-must use an inverter on the output.
         _
                                        I 0
 0
 0
                                             HALT HOLD
                                              D
        0
    0
                                    1
 0
            0
                    0
                0
                        0
 0
 0
 0
                            1
 0
                                1
 0
 0
 0
 0
 0
                                             A
                                         Y 7
 * Indicates an active low input—complement column or use an inverter on the input.
                            0
                                    0
    0
                                0
 0
 0
 0
 0
 0
                    1
 0
 0
        1
 0
 0
 0
                        1
                                         Y 6
                1
            1
                                             D
                                              D R
                                          w
                0
                                0
                                    0
 0
                            0
                        0
 0
 0
 0
 0
 0
            0
        0
                    1
 1
 1
                                             Lf
    1
 1
 1
                                             D r
                                    0
                                0
                0
        0
 0
 0
    0
 0
 0
                        0
                    0
            0
 0
 0
 0
 0
                            0
 0
 1
                                         Y 4
                                0
                        0
        0
                    0
                0
                            0
                                    0
 0
 0
 0
            0
 0
 0
 0
 0
    0
 0
 1
 1
                                         Y 3
                                            LUULY
 P-term table for the PLA implementation of the NS and output functions of the stepping motor controller expressed by Eqs. (13.19).
                                                    PLA Outputs
                                0
                                    0
    0
 0
 0
 0
                        0
                0
            0
                    0
        0
 0
 0
 0
                            0
 0
 0
 0
 1
                                         Y 2
                                             LDZERO ** . ?L E  v** DECDLY
                                    0
        0
                            0
                        0
                    0
            0
                                0
                0
    0
 0
 0
 0
 0
 0
 0
 0
 0
 0
                                         Y,
 1
                                             INCDLY
        0
                        0
            0
                0
                    0
                                0
 0
                                    0
                            0
    0
 0
 0
 0
 0
 0
 0
 0
                                         Y o
 1
 1
                                             STDLY
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