Cirrus Logic CDB42L55, Manual

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6 DS773DB1
CDB42L55
Configuration of the CS8416 is made using controls in the “Board Configuration” tab of the Cirrus FlexGUI
software.
Section 3 “Configuration Options” on page 8 and Section 4 “Software Mode Control” on page 10
provide configuration examples and software details.
2.3.2 CS8421 Sample Rate Converter (Tx SRC to CS42L55)
The CS8421 Tx SRC receives PCM digital audio data from either the CS8416 S/PDIF receiver or the AP
PSIA header and synchronizes this data with the CS42L55, regardless of the CS42L55’s master and au-
dio clocks.
A complete description of the CS8421 ( Figure 38 on page 26 ) and a discussion of the digital audio inter-
face can be found in the CS8421 data sheet.
Configuration and routing selections for the CS8421 are made using controls in the “Board Configuration”
tab of the Cirrus FlexGUI software.
Section 3 “Configuration Options” on page 8 and Section 4 “Software
Mode Control” on page 10 provide configuration examples and software details.
2.4 Digital Output
2.4.1 CS8406 S/PDIF Digital Audio Transmitter
The CS8406 converts the PCM data generated from the CS42L55 (through the “Receive” (Rx) SRC) to
the standard S/PDIF data stream.
A complete description of the CS8406 ( Figure 38 on page 26 ) and a discussion of the digital audio inter-
face can be found in the CS8406 data sheet.
Configuration of the CS8406 is made using controls in the “Board Configuration” tab of the Cirrus FlexGUI
software.
Section 3 “Configuration Options” on page 8 and Section 4 “Software Mode Control” on page 10
provide configuration examples and software details.
2.4.2 CS8421 Sample Rate Converter (Rx SRC from CS42L55)
The CS8421 Rx SRC receives PCM digital audio data from the CS42L55 and synchronizes this data with
either the CS8406 S/PDIF transmitter or the AP PSIA headers, regardless of the CS42L55’s master and
audio clocks.
A complete description of the CS8421 ( Figure 38 on page 26 ) and a discussion of the digital audio inter-
face can be found in the CS8421 data sheet.
Configuration and routing selections for the CS8421 are made using controls in the “Board Configuration”
tab of the Cirrus FlexGUI software.
Section 3 “Configuration Options” on page 8 and Section 4 “Software
Mode Control” on page 10 provide configuration examples and software details.
2.5 FPGA
The FPGA controls the digital signal routing between the CS42L55, CS8406, CS8416, CS8421 (Tx SRC
and Rx SRC), PLL and the I/O stake header.
Configuration and routing selections for the FPGA are made using controls in the “Board Configuration” tab
of the Cirrus FlexGUI software.
Section 4 on page 10 provides software configuration details.