SI4736-C40 Datasheet, PDF (26/42 Pages) Silicon Laboratories – BROADCAST AM/FM RADIO RECEIVER

Si4736/37/38/39-C40
5.17. Firmware Upgrades
The Si4736/37/38/39 contains on-chip program RAM to
accommodate minor changes to the firmware. This
allows Silicon Labs to provide future firmware updates
to optimize the characteristics of new radio designs and
those already deployed in the field.
5.18. Reset, Powerup, and Powerdown
Setting the RST pin low will disable analog and digital
circuitry, reset the registers to their default settings, and
disable the bus. Setting the RST pin high will bring the
device out of reset.
A powerdown mode is available to reduce power
consumption when the part is idle. Putting the device in
powerdown mode will disable analog and digital circuitry
while keeping the bus active.
5.19. Programming with Commands
To ease development time and offer maximum
customization, the Si4736/37/38/39 provides a simple
yet powerful software interface to program the receiver.
The device is programmed using commands,
arguments, properties, and responses.
To perform an action, the user writes a command byte
and associated arguments, causing the chip to execute
the given command. Commands control an action such
as powerup the device, shut down the device, or tune to
a station. Arguments are specific to a given command
and are used to modify the command. A partial list of
commands is available in Table 15, “Selected Si473x
Commands,” on page 27.
Properties are a special command argument used to
modify the default chip operation and are generally
configured immediately after powerup. Examples of
properties are de-emphasis level, RSSI seek threshold,
and soft mute attenuation threshold. A partial list of
properties is available in Table 16, “Selected Si473x
Properties,” on page 28.
Responses provide the user information and are
echoed after a command and associated arguments are
issued. All commands provide a 1-byte status update,
indicating interrupt and clear-to-send status information.
For a detailed description of the commands and
properties for the Si4736/37/38/39, see “AN332: Si47xx
Programming Guide.”
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