ldmicro.txt

用PIC單片機與AVR單片機製作PLC控制的階梯圖程序。

applications. Type in the frequency of the crystal that you will use
with the microcontroller (or the ceramic resonator, etc.) and click okay.

Now you can generate code from your program. Choose Compile -> Compile,
or Compile -> Compile As... if you have previously compiled this program
and you want to specify a different output file name. If there are no
errors then LDmicro will generate an Intel IHEX file ready for
programming into your chip.

Use whatever programming software and hardware you have to load the hex
file into the microcontroller. Remember to set the configuration bits
(fuses)! For PIC16 processors, the configuration bits are included in the
hex file, and most programming software will look there automatically.
For AVR processors you must set the configuration bits by hand.


INSTRUCTIONS REFERENCE
======================

> CONTACT, NORMALLY OPEN        Xname           Rname          Yname
                             ----] [----     ----] [----    ----] [----

    If the signal going into the instruction is false, then the output
    signal is false. If the signal going into the instruction is true,
    then the output signal is true if and only if the given input pin,
    output pin, or internal relay is true, else it is false. This
    instruction can examine the state of an input pin, an output pin,
    or an internal relay.


> CONTACT, NORMALLY CLOSED      Xname           Rname          Yname
                             ----]/[----     ----]/[----    ----]/[----

    If the signal going into the instruction is false, then the output
    signal is false. If the signal going into the instruction is true,
    then the output signal is true if and only if the given input pin,
    output pin, or internal relay is false, else it is false. This
    instruction can examine the state of an input pin, an output pin,
    or an internal relay. This is the opposite of a normally open contact.


> COIL, NORMAL                  Rname           Yname
                             ----( )----     ----( )----

    If the signal going into the instruction is false, then the given
    internal relay or output pin is cleared false. If the signal going
    into this instruction is true, then the given internal relay or output
    pin is set true. It is not meaningful to assign an input variable to a
    coil. This instruction must be the rightmost instruction in its rung.


> COIL, NEGATED                 Rname           Yname
                             ----(/)----     ----(/)----

    If the signal going into the instruction is true, then the given
    internal relay or output pin is cleared false. If the signal going
    into this instruction is false, then the given internal relay or
    output pin is set true. It is not meaningful to assign an input
    variable to a coil.  This is the opposite of a normal coil. This
    instruction must be the rightmost instruction in its rung.


> COIL, SET-ONLY                Rname           Yname
                             ----(S)----     ----(S)----

    If the signal going into the instruction is true, then the given
    internal relay or output pin is set true. Otherwise the internal
    relay or output pin state is not changed. This instruction can only
    change the state of a coil from false to true, so it is typically
    used in combination with a reset-only coil. This instruction must
    be the rightmost instruction in its rung.


> COIL, RESET-ONLY              Rname           Yname
                             ----(R)----     ----(R)----

    If the signal going into the instruction is true, then the given
    internal relay or output pin is cleared false. Otherwise the
    internal relay or output pin state is not changed. This instruction
    instruction can only change the state of a coil from true to false,
    so it is typically used in combination with a set-only coil. This
    instruction must be the rightmost instruction in its rung.


> TURN-ON DELAY                 Tdon 
                           -[TON 1.000 s]-

    When the signal going into the instruction goes from false to true,
    the output signal stays false for 1.000 s before going true. When the
    signal going into the instruction goes from true to false, the output
    signal goes false immediately. The timer is reset every time the input
    goes false; the input must stay true for 1000 consecutive milliseconds
    before the output will go true. The delay is configurable.

    The `Tname' variable counts up from zero in units of scan times. The
    TON instruction outputs true when the counter variable is greater
    than or equal to the given delay. It is possible to manipulate the
    counter variable elsewhere, for example with a MOV instruction.


> TURN-OFF DELAY                Tdoff 
                           -[TOF 1.000 s]-

    When the signal going into the instruction goes from true to false,
    the output signal stays true for 1.000 s before going false. When
    the signal going into the instruction goes from false to true,
    the output signal goes true immediately. The timer is reset every
    time the input goes false; the input must stay false for 1000
    consecutive milliseconds before the output will go false. The delay
    is configurable.

    The `Tname' variable counts up from zero in units of scan times. The
    TON instruction outputs true when the counter variable is greater
    than or equal to the given delay. It is possible to manipulate the
    counter variable elsewhere, for example with a MOV instruction.


> RETENTIVE TIMER               Trto  
                           -[RTO 1.000 s]-

    This instruction keeps track of how long its input has been true. If
    its input has been true for at least 1.000 s, then the output is
    true. Otherwise the output is false. The input need not have been
    true for 1000 consecutive milliseconds; if the input goes true
    for 0.6 s, then false for 2.0 s, and then true for 0.4 s, then the
    output will go true. After the output goes true it will stay true
    even after the input goes false, as long as the input has been true
    for longer than 1.000 s. This timer must therefore be reset manually,
    using the reset instruction.

    The `Tname' variable counts up from zero in units of scan times. The
    TON instruction outputs true when the counter variable is greater
    than or equal to the given delay. It is possible to manipulate the
    counter variable elsewhere, for example with a MOV instruction.


> RESET                        Trto             Citems
                           ----{RES}----     ----{RES}----

    This instruction resets a timer or a counter. TON and TOF timers are
    automatically reset when their input goes false or true, so RES is
    not required for these timers. RTO timers and CTU/CTD counters are
    not reset automatically, so they must be reset by hand using a RES
    instruction. When the input is true, the counter or timer is reset;
    when the input is false, no action is taken. This instruction must
    be the rightmost instruction in its rung.


> ONE-SHOT RISING                  _
                           --[OSR_/ ]--

    This instruction normally outputs false. If the instruction's input
    is true during this scan and it was false during the previous scan
    then the output is true. It therefore generates a pulse one scan
    wide on each rising edge of its input signal. This instruction is
    useful if you want to trigger events off the rising edge of a signal.


> ONE-SHOT FALLING               _
                           --[OSF \_]--

    This instruction normally outputs false. If the instruction's input
    is false during this scan and it was true during the previous scan
    then the output is true. It therefore generates a pulse one scan
    wide on each falling edge of its input signal. This instruction is
    useful if you want to trigger events off the falling edge of a signal.


> SHORT CIRCUIT, OPEN CIRCUIT
                           ----+----+----      ----+     +----

    The output condition of a short-circuit is always equal to its
    input condition. The output condition of an open-circuit is always
    false. These are mostly useful for debugging.


> MASTER CONTROL RELAY
                           -{MASTER RLY}-

    By default, the rung-in condition of every rung is true. If a master
    control relay instruction is executed with a rung-in condition of
    false, then the rung-in condition for all following rungs becomes
    false. This will continue until the next master control relay
    instruction is reached (regardless of the rung-in condition of that
    instruction). These instructions must therefore be used in pairs:
    one to (maybe conditionally) start the possibly-disabled section,
    and one to end it.


> MOVE                      {destvar :=  }      {Tret :=     }
                           -{ 123     MOV}-    -{ srcvar  MOV}-

    When the input to this instruction is true, it sets the given
    destination variable equal to the given source variable or
    constant. When the input to this instruction is false nothing
    happens. You can assign to any variable with the move instruction;
    this includes timer and counter state variables, which can be
    distinguished by the leading `T' or `C'. For example, an instruction
    moving 0 into `Tretentive' is equivalent to a reset (RES) instruction
    for that timer. This instruction must be the rightmost instruction
    in its rung.


> ARITHMETIC OPERATION       {ADD  kay  :=}       {SUB  Ccnt :=}
                            -{ 'a' + 10   }-     -{ Ccnt - 10  }-

>                            {MUL  dest :=}       {DIV  dv :=  }
                            -{ var * -990 }-     -{ dv / -10000}-

    When the input to this instruction is true, it sets the given
    destination variable equal to the given expression. The operands
    can be either variables (including timer and counter variables)
    or constants. These instructions use 16 bit signed math. Remember
    that the result is evaluated every cycle when the input condition
    true. If you are incrementing or decrementing a variable (i.e. if
    the destination variable is also one of the operands) then you
    probably don't want that; typically you would use a one-shot so that
    it is evaluated only on the rising or falling edge of the input
    condition. Divide truncates; 8 / 3 = 2. This instruction must be
    the rightmost instruction in its rung.


> COMPARE               [var ==]        [var >]        [1 >=]
                       -[ var2 ]-      -[ 1   ]-      -[ Ton]-

>                       [var /=]       [-4 <   ]       [1 <=]
                       -[ var2 ]-     -[ vartwo]-     -[ Cup]-

    If the input to this instruction is false then the output is false. If
    the input is true then the output is true if and only if the given
    condition is true. This instruction can be used to compare (equals,
    is greater than, is greater than or equal to, does not equal,
    is less than, is less than or equal to) a variable to a variable,
    or to compare a variable to a 16-bit signed constant.


> COUNTER                      Cname          Cname
                           --[CTU >=5]--  --[CTD >=5]--

    A counter increments (CTU, count up) or decrements (CTD, count