Digital PMR Radio Processor
CMX7131/CMX7141
note:
Data is in 9 byte blocks
Rx_Process
Set Modem Control to:
Rx 4FSK, Mode = Rx
GPIO2 and GPIO1 will change to 10, the Modem will start to look
for frame sync. The host should ensure that any external
hardware is also set into Rx mode (if not automatically controlled
by the GPIO pins).
note:
If enabled , IRQ=FrameSync
note:
will occur before
IRQ=DataRdy
No
IRQ = DataRdy?
yes
Load data from C-BUS
RxDataBlock
check transaction count
and byte count
more data to
receive?
No
An IRQ=DataRdy
note:
may still be
pending at this
point
yes
Set Modem Control to:
RxIdle, Mode = Idle
Goto Tx_Process
See Tx_Process Flow
Diagram
GPIO2 and GPIO1 will change to 11, and
the Modem will drop into Idle mode. The
host should ensure that any external
note:
note:
hardware is also set into Idle mode (if not
automatically controlled by the GPIO pins).
Goto Idle_Process
Figure 22 Rx Data Flow
2014 CML Microsystems Plc
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