FX929B Datasheet, PDF (32/48 Pages) CML Microcircuits – Flexible Operating Modes

4-Level FSK Modem Data Pump
FX929B
Figures 16a and 16b illustrate the host µC routines needed to send a single Frame consisting of Symbol and
Frame Sync patterns, a Station ID block, a Header block, any number of Intermediate blocks and one Last
block. It is assumed that the Tx Interrupt Service Routine (Figure 16b) is called whenever the FX929B's IRQN
output line goes low.
Figure 16a Transmit Frame Example Flowchart, Main Program
Note that the RESET command in Figure 16a and the practice of disabling the FX929B's IRQN output when
not needed are not essential but can eliminate problems during debugging and if errors occur in operation.
Note also that the CRC and TXIMP bits should be set appropriately whenever a byte is written to the
Command Register.
© 1997 Consumer Microcircuits Limited
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D/929B/1