TDA5235 Datasheet, PDF (104/259 Pages) Infineon Technologies AG – Enhanced Sensitivity Double-Configuration Receiver with Digital Baseband Processing

TDA5235
Functional Description
2.6.1.6 Automatic Modulation Switching
In Self Polling Mode, the chip is able to automatically change the type of modulation
after a wake-up criterion was fulfilled in a received data stream. The type of modulation
used in the different operational modes is selected by the SFR control bit MT.
2.6.1.7 Multi-Channel in Self Polling Mode
A simple Multi-Channel behavior can be realized when the same application parameters
are programmed in both Configuration sets and only the RF PLL frequency differs.
Channel frequencies are defined in registers x_PLLINTC1, x_PLLFRAC0C1,
x_PLLFRAC1C1, x_PLLFRAC2C1, where x = A or B.
See also Chapter 2.4.5 Sigma-Delta Fractional-N PLL Block.
2.6.1.8 Run Mode Self Polling (RMSP)
The chip enters Run Mode Self Polling after a successful fulfillment of a wake-up
criterion in Self Polling Mode.
When Wake-Up criterion for RSSI or Signal Recognition (see Chapter 2.4.8.1) is
selected and fulfilled, this leads to a change to Run Mode Self Polling. This will be
interesting especially in case of a transparent data stream being processed externally by
the Application Controller (see Chapter 2.5.1.2 Data Interface).
The following steps are performed automatically, depending on register settings:
• Modulation switching (see Chapter 2.6.1.6 Automatic Modulation Switching)
• Wait for valid TSI (see Chapter 2.4.8.6 Frame Synchronization)
• Initialize FIFO (see Chapter 2.5.2 Receive FIFO) and write data to FIFO
• Scan for MIDs (see Chapter 2.4.8.7 Message ID Scanning)
Depending on interrupt masking, the host microcontroller is alerted when
• a data frame has started,
• an MID has been found, (if enabled) or
• EOM (End of Message) has been detected.
See also Chapter 2.5.4 Interrupt Generation Unit
Run Mode Self Polling is left, when synchronization is lost and the timeout timer for loss
of synchronization (TOTIM_SYNC) has elapsed, or when one of the other timeout timers
(TOTIM_TSI, TOTIM_EOM) for each configuration (A, B) has elapsed, or when an EOM
occurred and the SFR bit EOM2SPM is activated, or when the operating mode is
switched to SLEEP or Run Mode Slave by the host microcontroller.
Data Sheet
104
V1.0, 2010-02-19