+-------+                       +-------+
T.CSR:  |       |--+            RCSR:   |   0   |
        +-------+  |                    +-------+
                   |            RDAT:   |       |
                   |                    +-------+
                   |            XCSR:   |   0   |
                   |                    +-------+
                   |            XDAT:   |       |
                   |                    +-------+
                   |
                   |            +--------+
                   |    OTCSR:  | RCSR   |
                   |            +--------+
                   |    PTTPS:  |c(XCSR) |
                   |            +--------+
                   +--> TTKS:   |c(RCSR) |
                                +--------+
                        TTKB:   |        |
                                +--------+
                        TTPS:   |c(XCSR) |
                                +--------+
                        TTPB:   |        |
                                +--------+
 
 
                                +--------+
                        OXTTNR: | TNRRTN |
        +-------+               +--------+
$XTTNR: |       |-----> XTTNR:  Simulated action routine for no input space
        +-------+
 
                                +--------+
                        OXTTPS: | TPSRTN |
        +-------+               +--------+
$XTTPS: |       |-----> XTTPS:  Simulated XCSR action routine
        +-------+
 
                                +--------+
                        OXTTPB: | TPBRTN |
        +-------+               +--------+
$XTTPB: |       |-----> XTTPB:  Simulated XDAT action routine
        +-------+