TUSB1064RNQEVM: Can't establish I2C communication with TPS65986

Jarratt Burch

Part Number: TUSB1064RNQEVM
Other Parts Discussed in Thread: TPS65981

I am using the TUSB1064RNQEVM and attempting to configure it so that it uses the DisplayPort Alternate Mode to output a video signal at P3 and simultaneously output USB data at P2. In the board's default configuration, when I connect a USB cable to P1 and a display to P3 there is no video present on the display.

I have been attempting to adjust the Power Delivery settings of the TPS65986 by changing parameters via an I2C connection and tried the following two methods:

1. With the jumper at JMP7 connecting I2C_EN to VCC, I connected an FTDI adapter (w/ associated driver installed) from my computer's USB port to the SDA/SCL pins on the evaluation board's JMP8 and the FTDI's ground wire to the board's GND connection at J5. After connecting a USB-C cable to P1 and verifying 5V was present on the VBUS, I opened the TPS65981 Application Customization program on my PC. I selected the "Configure I2C/SPI Adapter Settings" option, selected FTDI as the desired adapter, and chose the test "Sweep I2C Address Range for device response". I then received the error:

"Exception Encountered during I2C Address Sweep:*** ERROR in FTDI call (I2C_OpenChannel), status: 1

<type 'exceptions.Exception'>"

"Traceback (most recent call last):

File "dialogWindow.pyc", line 10787, in sweep_handler

File "hw_interface.pyc", line 185, in hw_open

Exception"

2. With the JMP7 jumper connecting I2C_EN to VCC, I setup an Arduino Due development board for I2C communication and have code to scan the connected I2C bus and report all acknowledgements. Wires from the Arduino were connected to the TUSB1064RNQEVM's JMP8 SDA & SCL pins as well as a ground wire connected to J5 GND pin. When my Arduino begins to poll I2C address on the TUSB1064RNQEVM, there are no acknowledgements and no other signs of communication.

Attached is a picture of my setup. When a USB cable is connected to P1, I have verified that 5V is present from J5 VBUS to J5 GND. Is there anything that I am missing in my setup in order to establish an I2C connection?

Thank you.

over 2 years ago

0 Brian Zhou over 2 years ago

TI__Guru** 119435 points

0 Brian Zhou over 2 years ago in reply to Brian Zhou

TI__Guru** 119435 points

0 Brian Zhou over 2 years ago in reply to Brian Zhou

TI__Guru** 119435 points

looks like you connect I2C wire at the wrong place, should be on SCL/SDA

0 Jarratt Burch over 2 years ago in reply to Brian Zhou

Prodigy 20 points

Thank you for your response.

I disconnected the leads from JMP8 and connected them to SCL on J1, SDA on J2 as you suggested. I also connected the ground lead from my FTDI adapter to the GND pin on J2. After reperforming both methods mentioned in my original post, I still was not able to receive any acknowledgements from any devices on the I2C bus when polling the range of valid addresses.

Are there any settings on the SW1 dipswitch that I need to adjust in order to access I2C addresses? I have not been able to find any information on this switch.

0 Brian Zhou over 2 years ago in reply to Jarratt Burch

TI__Guru** 119435 points

set DPEQ0(A1) and SSEQ0(A0) to L and I2C address:44 and try again

0 Jarratt Burch over 2 years ago in reply to Brian Zhou

Prodigy 20 points

Thank again for your response.

I set both DPEQ0(A1) and SSEQ0(A0) to Low but I still do not get an Ack from address 44. I tried with my Arduino board and with the TPS65981 Application Customization Tool (w/ FTDI adapter) but do not get a response.