TPS65982-EVM as Consumer - Reset problem

Hai,

When you received the TPS65982-EVM boards, did you go to the TPS65982 product folder and download the most recent TPS6598X-CONFIG configuration tool?

In every version of the Config Tool, there is an option to download an EVM recovery file that is updated to the latest FW version and install it on your EVM's SPI Flash IC.

Do you have a TotalPhase Aardvark I2C/SPI Master? This is the hardware we typically recommend to perform the Flash update directly over SPI.

For field FW updates, we use the TPS65982 I2C commands to pass data on to the SPI Flash and over-write the memory with a new FW version.

Hi Brian,

Thanks for prompt reply. Yes, I used the latest Config tool and update firmware for my EVM boards, with the binary firmware file that comes together with Config tool. I will show the datalog from Python script "read_registers" later.

I think that the problem might relate to Hard Reset condition, where the Consumer device, if it detects Over-Voltage on VBUS (still 12V/20V right after we press reset button), must send the Hard Reset message to Provider/Host, then Host will reset the voltage on VBUS accordingly and start new PD contract. However, I nearly found nothing in the current documents about this Hard Reset handling. 

Or maybe, I miss something here. Hope you can help to confirm the result of test case I posted. It relates to a product that we design based on TPS65986. Thanks.

Hi Brian,

Some information might be useful to understand more about the issue. When Consumer-EVM board is resetted and getting hanged, I measured some pins of TPS65982 and found that:

1) LDO_BMC is 0V (while it should be 1.125V as normal). It shouldn't be okay, right?

2) There's no valid signal on C_CCn line, instead, it looks strange to me as there are 3.3V spikes. Shown in picture below, channel 1 is C_CCn, channel 2 is SPI_CLK (that I want to show that TPS65982 keeps resetting and loading firmware from Flash IC each time).

Hi,

My latest testing results seem to prove that this issue relates to Hard Reset.

1) When VBUS is 5V or 12V or 20V, on the Sink device, I use python command "send_messages" in order to issue Hard Reset message to far-end device (here it's the Source). Source well recognizes the message and does reset VBUS to 0V then new PD contract is established correctly.

2) When VBUS is 5V, instead of python command, I press switch S3 on EVM board, it causes hardware reset. Then, from oscilloscope, I notice that TPS65982 issues Hard Reset message on C_CCn line. Same as above, Source device accepts it and reset VBUS.

3) When VBUS is 12V or 20V, if I press switch S3, no Hard Reset message on C_CCn line was seen on oscilloscope. This is the issue that I posted in 1st post.

What could be the reason why in case (3), TPS65982 does not generate Hard Reset message like (2), is it because VBUS is not 5V (i.e. vSafe5V as stated in USB PD spec)? Is there something in hardware or configuration (via Config Tool) that I can change to fix it. Please advice. Thank you.