Minimum number of pins to connect Teensy 3.2 and Audio Board

[jannone]

Dear All,

I just attempted to connect my Teensy 3.2 with an Audio Board, and got no output from the tutorial files.
Since I am trying to conserve pins, I'm attempting to connect using the minimum number.
I'm not using the SD Socket, so I connected the following pins:

SDA
SCL
+3.3V
LRCLK
TX
RX
GND
BCLK
MCLK

Should these 9 connections be sufficient? If so, I must have some other problem. If not, which additional pins need to be connected for use of the board without the SD Socket.

Thank you!

John

 

[PaulStoffregen]

Yes, those 9 are the minimum.

Actually, you can omit the RX connection if you only want to output sound to the headphone jack or line-out pins, or omit the TX connection if you only want sound input from the mic or line-in pins.

 

[MichaelMeissner]

Just to be clear, by RX/TX, you meant the I2S RX/TX pins and not the Serial1 UART pins (0/1):

• I2S TX (22/A8);
• I2S RX (13).

You probably need the SPI pins:

• Alternate MOSI (7);
• MISO (12);
• Alternate SCLK (14/A0);
• SD CS (10);
• and optionally Flash CS (6).

I would suspect it would be a good idea to connect VIN and AGND as well. If you want to attach a potentiometer on the board, you would need to connect pin 15/A1 as well.

The schematic lists 2.2K pull-up resistors on SDA/SCL, so you don't need to put your own in.