MAX 10 Plus User
Manual
62
May 31, 2019
software needed for Micro SD Card access and professional audio performance so that it is possible
to design advanced multimedia products using the MAX 10 Plus board.
shows the diagram of this demonstration. In this demonstration we show how to
implement an SD Card Music Player on the MAX 10 Plus board, in which the music files are stored
in an SD Card and the board can play the music files via its high-quality and low power audio DAC
circuits. We use the Nios II processor to read the music data stored in the SD Card and use
theTLV320AIC3254 audio CODEC to play the music.
Figure 6-12 System of SD Card Audio Demo
shows the hardware block diagram of this demonstration. The system requires a 50
MHz clock provided from the board. The PLL generates a 100MHz clock for Nios II processor and
the other controllers. The audio chip is controlled by the Audio Controller which is a user-defined
SOPC component. The internal PLL in the CODEC chip can generate the clock rate according to
the sample rate of the music. A mater clock should be supplied for the CODEC. The mater clock
rate in this demonstration is 19.2M provided by the PLL block in FPGA. The audio controller
requires the audio chip working in master mode, so the serial bit (BCLK) and the word clock
(WCLK) are provided by the audio chip. An OpenCore I2C controller is connected to the CODEC
chip for the Nios II CPU to communicate with the CODEC chip. Four PIO pins are connected to the
micro SD Card socket. SD 4-Bit Mode is used to access the micro SD Card and is implemented by
software. All the other SOPC components in the block diagram are SOPC Builder built-in
components. The PIO pins are also connected to the keys, LEDs and switches.