ocm5.gv

digraph ocm5 {
    edge [ decorate = true ]
    node [
        style = filled
        colorscheme=dark28
    ]
    RAM [ fillcolor = 1 ]
    subgraph IOPorts {
        node [ fillcolor = 2 ]
        IN [ label = "<IN>" ]
        OUT [ label = "<OUT>" ]
    }
    subgraph Registers {
        node [ fillcolor = 3 ]
        A [ label = "[A]" ]
        B [ label = "[B]" ]
    }
    subgraph Banks {
        node [ fillcolor = 4 ]
        OPERATOR [ label = "[@]" ]
        LOCATION [ label = "[#]" ]
    }
    subgraph Signals {
        node [ fillcolor = 5 ]
        POWER [ label = "{POWER}" ]

        OVERFLOW [ label = "{OVERFLOW}" ]

        GO [ label = "{GO}" ]
        POWER -> GO [ label = "condition of "]
        GO -> {
            LOCATION ->
            RAM ->
            OPERATOR [ label = "send data on {GO}" ]
        } [ label = "Update [@] to number at [#] in RAM"]

        ROTATEONE [ label = "{ROTATEONE}" ]
        ROTATEONE -> LOCATION [ label = "Increases by one" ]

        STEP [ label = "{STEP}" ]
        STEP -> ROTATEONE [ label = "1. Triggers first" ]
        STEP -> GO [ label = "2. Triggers second" ]
    }
    subgraph Instructions {
        OPERATOR -> {
            NOP
            HALT
            SWAP
            NEXT
            GET
            SET
            IFGOTO
            READIN
            SENDOUT
            ADD
            SUBTRACT
        } [ label = "Decode" ]

        edge [colorscheme=paired12]
        edge [ color = 1 ]
        NOP -> STEP [ label = "Triggers" ]
        
        edge [ color = 2 ]
        HALT -> POWER [ label = "Sets to OFF" ]
        
        edge [ color = 3 ]
        SWAP -> {
            A -> B [ label = "send data on SWAP" ]
            B -> A [ label = "send data on SWAP" ]
        } [ label = "1. Swap values stored in [A] and [B]"]
        SWAP -> STEP [ label = "2. Trigger last"]
        
        edge [ color = 4 ]
        NEXT -> ROTATEONE [ label = "1. Trigger first" ]
        NEXT -> {
            LOCATION -> RAM -> A [ label = "send data on NEXT" ]
        } [ label = "2. Set [A] to number at [#] in ram" ]
        NEXT -> STEP [ label = "3. Trigger last"]
        
        edge [ color = 5 ]
        GET -> {
            B -> RAM -> A [ label = "send data on GET"]
        } [ label = "1. Set [A] to the number at [B] in ram"]
        GET -> STEP [ label = "2. Trigger last"]
        
        edge [ color = 6 ]
        SET -> {
            { B; A } -> RAM [ label = "send data on SET"]
        } [ label = "1. Set set number at [B] in the ram to [A]" ]
        SET -> STEP [ label = "2. Trigger last" ]
        
        edge [ color = 7 ]
        OVERFLOW -> {
            IFGOTO -> { B -> LOCATION } [ label = "1. Set [#] to [B]" ]
            IFGOTO -> GO [ label = "2. Trigger last"]
        } [ label = "condition of "]
        OVERFLOW -> {
            IFGOTO -> STEP [ label = "Triggers"]
        } [ label = "inverse condition of"]
        
        edge [ color = 8 ]
        READIN -> {
            IN -> A [ label = "send data on READIN" ]
        } [ label = "1. Set [A] to <IN>" ]
        READIN -> STEP [ label = "2. Trigger last" ]

        edge [ color = 9 ]
        SENDOUT -> {
            A -> OUT [ label = "send data on SENDOUT" ]
        } [ label = "1. Set <OUT> to [A]" ]
        SENDOUT -> STEP [ label = "2. Trigger last" ]

        edge [ color = 10 ]
        ADD -> {
            { A; B } -> A [ label = "add values on ADD" ]
        } [ label = "1. Change [A] to it's old value plus [B]"]
        ADD -> OVERFLOW [ label = "2. If there was an overflow, set {OVERFLOW}, or else unset it."]
        ADD -> STEP [ label = "3. Trigger last" ]

        edge [ color = 11 ]
        SUBTRACT -> {
            { A; B } -> A [ label = "subtract values on SUBTRACT" ]
        } [ label = "1. Change [A] to it's old value minus [B]" ]
        SUBTRACT -> OVERFLOW [ label = "2. If there was an underflow, set {OVERFLOW}, or else unset it." ]
        SUBTRACT -> STEP [ label = "3. Trigger last" ]
    }
}