Motorola DSP56309 User Manual page 195

Enhanced Synchronous Serial Interface (ESSI)
ESSI Programming Model
7.4.3.8 ESSI Receive Data Register Full (RDF) Bit 7
The RDF bit is set when the contents of the receive shift register are transferred to the
receive data register. The RDF bit is cleared when the DSP reads the receive data
register. If RIE is set, a DSP receive data interrupt request is issued when RDF is set. A
hardware RESET signal, software RESET instruction, ESSI individual reset, or STOP
instruction clears the RDF bit.
The ESSI data path programming models are shown in Figure 7-16 on page 7-31 and
Figure 7-17 on page 7-32.
7-30 DSP56309UM/D MOTOROLA