2.4.5 Master Control Unit
The Master Control Unit controls the operation modes, the global states, and is generally
responsible for automating data reception, verification, identification, extraction, and
storage into the FIFO. The data without RUNIN and TSI are read via SPI from the FIFO
by the external microcontroller.
The following operational modes and the behavior of the Master Control Unit are fully
automatic and influenced only by SFR settings and by incoming RF streams.
The TDA523x has two major operational modes. Modes are switched by the SFR bit
In Slave Mode the device is controlled via SPI by the external microcontroller. This mode
• Run Mode Slave, where the receiver is continuously active
• Sleep Mode, where the receiver is switched off for power saving. This mode can also
be used to change register settings
• Hold Mode, allows to register settings to be changed. The change to Hold Mode and
back is faster than changing to Sleep Mode.
Switching between configurations and channels, as well as in between Run and Sleep
mode must be initiated by the microcontroller.
In Self Polling Mode TDA523x autonomously polls for incoming RF signals. The
receiver switches automatically between the two configurations (Configuration A and
Configuration B) and up to 3 channels per configuration (Further information is located
in Chapter 2.4.6 Polling Timer Unit).
Between scans, the receiver is automatically switched off to save power. If an incoming
signal fulfills the selected wake-up criteria, matches the TSI pattern, and passes the
optional message ID screening, the payload is loaded into the FIFO, and, if not masked,
an interrupt is generated. Then, the payload data can be read via SPI.
Version 4.0, 2007-06-01