SI47XX-EVB Datasheet, PDF (57/164 Pages) Silicon Laboratories – Thank you for purchasing the Silicon Laboratories

Si47xx-EVB
5.10.2. Intermediate
In the intermediate section, we will cover the buffers category of sending the RDS data with the device, in particular
we will send Group Type 2 (Radio Text) and Group Type 4 (Clock Time).
The following diagram shows a step-by-step procedure to send the buffers data in addition to the General and
Program Service data covered in the basic section.
1
2
3a
3
5
6
4
Figure 47. Intermediate RDS Message Illustration
1. Select the Mix percentage that you want between transmitting the data in Program Service and the data in
the Buffers. A mix percentage of 100% means that you will always transmit the PS message regardless of
what is contained in the Buffers, whereas a mix percentage of 0% means that you will always transmit the
data in the Buffers regardless of what is contained in the PS. If the buffers are empty, the PS messages will
be transmitted all the time regardless of the mix percentage.
2. Enter the Radio Text message that will be transmitted. After entering the RT message, click either the "Add
to Circular" button or the "Add to FIFO" button. The RT message will be encoded according to the RDS
Group Type 2 rule.
a. Clicking "Add to Circular" button means that you add the RT message into the GUI Circular Buffer
queue. Note that the message itself has not been uploaded into the Circular Buffer inside the device
until the Clear Buff & Send is clicked.
b. Clicking "Add to FIFO" means that you upload the RT message into the GUI FIFO Buffer queue. Note
that the message itself has not been uploaded into the FIFO Buffer inside the device until the Clear
Buff & Send is clicked.
3. Enter the size of the FIFO that you want here. The device buffer has a total of 128 blocks, which is shared
by the circular buffer and the FIFO. Therefore, the circular buffer size (shown in 3a) will be the remainder of
the 128 blocks minus the FIFO size.
4. Clicking this "Clear Buff & Send" button will upload the message from the GUI Circular Buffer queue into
the Circular Buffer inside the device. The Circular Buffer on the part will repeatedly send the message
contained in the buffer. Note that the messages in the circular buffer will be transmitted only if the PS Mix
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