How to connect an I2S peripheral to TWR K65F180M Board ?

[balaji_ch]

I am trying to stream audio from the TWR K65F180M to an external I2S device. I am unable to find the pins on the board .

[xiangjun_rong · Accepted solution]

Hi, Balaji,

Pls see the table 11-47, there is only one I2S module for K65, the I2S signal list is displayed in table 11-47.

On the TWR-K65F180 board, there is not dedicated connector which can route the I2S signals, you have to use primary elavator board and connect the I2S signals out from primary elavator board.

Note that the DNP means "Do Not Populate", for example R131 and R133 are not populated, so the I2S0_RXD1 and I2S0_TXD1 can not be connected if you do not solder the resistors.

Hope it can help you

BR

Xiangjun Rong

[balaji_ch]

I have to connect another board(RPi3) to this K65F.  K65F (master) has to send some pcm samples via I2S to I2S enabled RPi3(slave).
Could you please correct me if I am wrong in the pin conncections?

BitClock of RPi3 to I2S0_Tx_Bclk of K65

LRClk of RPi3 to I2S0_Tx_FS
DIn of RPi3 to I2S0_Tx_D0

I am following the pinouts mentioned in this pdf
http://www.nxp.com/assets/documents/data/en/user-guides/TWRK65F180MUG.pdf 

[xiangjun_rong]

Hi,

BitClock of RPi3 to I2S0_Tx_Bclk of K65

LRClk of RPi3 to I2S0_Tx_FS
DIn of RPi3 to I2S0_Tx_D0

I think your above connection is correct.

BR

Xiangjun Rong

[balaji_ch]

Hi Xiangjun,

Thank you. :smileylaugh:

Using the following example
C:\Users\admin\Documents\SDK_2.1_TWR-K65F180M\boards\twrk65f180m\demo_apps\sai
I could see all the clocks on the Oscilloscope.
The example has 16KHz 16bit 2 Channel pcm samples and I could verify the following.
A21 pin = mclk = 6.144 MHz (384*16K)

A22 pin = bclk (aka serial clock)= 1 MHz (16*32*2)  even the samples are 16 bit . {The reason seems to be "In Master mode, word length is fixed to be 32. The number of valid data bits in the word can be set, but while computing the bit rate, it must be set to 32." as  per page 4 of  http://www.nxp.com/assets/documents/data/en/application-notes/AN4520.pdf  }
A23 pin = fs(aka lrclk) = 16KHz