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TLM 2.0 supports the annotation of time to transactions. The EVS does not honor such timing as described by the scenarios shown in Figure 5.18 and Figure 5.19.
For Figure 5.18,
the component in the EVS Core issues a read transaction to the SystemC
component Memory. The transaction immediately returns annotating
a delay of 10ns. The EVS ignores this annotation and continues the
execution (read transaction #2) for the time quantum as if the memory
had responded with a SC_ZERO_TIME
delay.
For Figure 5.19,
a transaction is issued by a component in the SystemC domain (Core) that
accesses a memory modeled in the EVS (Memory). The timing annotation
of the transaction is never be changed by the EVS because it runs
in a temporal-decoupled way that assumes all transactions are handled
immediately. Figure 5.19 shows
two read transactions that are issued by a DMA component. The first
transaction, marked with SC_ZERO_TIME, is
answered
by the memory component in the EVS immediately. Therefore the timing
annotation is not changed. The second transaction is similar and the
annotation of 10ns is also not changed by the memory component.
This behavior is inherent to the temporal decoupled fast models
and does not change for future releases.