The TI E2E™ design support forums will undergo maintenance from July 11 to July 13. If you need design support during this time, open a new support request with our customer support center.

  • State
  • Replies 2 replies
  • Subscribers 63 subscribers
  • Views 41 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

Original question:

BQ79616: Does enabling the UART_MIRROR_EN bit allows responses coming from UART to be forwarded through the VIF?

BQ79616: UART_MIRROR_EN message forwarding functionality clarification

Lucas Freitas
Prodigy 20 points
Part Number: BQ79616
Other Parts Discussed in Thread: BQ79600EVM, USB2ANY,

Tool/software:

I'm currently using a setup with a USB2ANY (connected to the bridge), a BQ79616EVM (as a stack device), a BQ79600EVM (as the bridge) and a LaunchXL2-TMS57102 (UART device). Using the UART_MIRROR_EN debug feature I'm trying to forward a VIF to UART message, but with no success. I enable the feature and try auto-addressing using the BQAutoEval GUI and forward the VIF to UART data but it does not work.

I then tried checking if any data was being sent on the RX/TX lines on both connectors J3 and J17 using a logic analyzer and I saw data coming out of it from J17 but not J3. The data wasn't anything I sent via the GUI. At first both lines were high as in standby mode, but then when I connected to pin 6 (USB2ANY_3.3V) I started seeing data back again. Here are my questions:

- In order to be able to forward any data using the UART_MIRROR_EN debug feature, is it necessary to give an address to the UART device?

- Is the forwarding only replicating data that is going on inside BQ79616EVM, or can it actually send data to an address set to the UART device?

- Since I only see data when I have pin 6 (USB2ANY_3.3V) connceted, does it need to have voltage going on? Would that be why I cannot see data on J3 since it only has GND (pin 1)?

- If I use the BQ79616EVM as the bridge with the USB2ANY, should I still be able to do the forwarding using J3?

*When a connection is done to GND to have a common ground the stack device is turned off

  • 0
    TI__Intellectual 1160 points

    Hi Lucas,

    The UART_MIRROR_EN feature will mirror received VIF response frames and send them to UART.

    1. Please ensure that correct procedure is used. Autoaddressing should be done prior to setting UART_MIRROR_EN. First, the DEBUG_CTRL_UNLOCK 0x700 register should be unlocked in order to use the UART_MIRROR_EN test mode. Second, write to DEBUG_COMM_CTRL1 and ensure UART_MIRROR_EN, UART_TX_EN, and USER_UART_EN bits are set.

    2. Can you please specify how you connected the RX/TX pins to logic analyzer? Typically it's just RX, TX, GND.

    3. When connected to BQ79616EVM as bridge with USB2ANY, J3 will still be able to forward. (Note UART_MIRROR_EN is designed for stack devices)

    Best Regards,

    John

  • 0 in reply to John Du
    Prodigy 20 points

    Hi John, 

    Thank you very much for your reply.

    Just to clarify, by my understanding I thought with the mirroring feature I would be able send commands (such as single write, stack write and broadcast write) through this feature at the stack. So the only information I'll receive is the response frames from the devices that are on the stack, rather then forward write commands as well?

    I was able to see data using the BQ79616 as a base device through the logic analyzer and see the response frames, for the commands sent I see the moment they happened but not what it was, only FF when I get closer. Is that behavior expected? Is it still forwarding the commands to other devices if I were to connect them to the stack via UART?

    1.I will follow it as you said and then let you know.

    2. I have a breakout box connected to a code just running high signal to connect to the pin 6 (USB2ANY_3.3V) and a GND from the breakout box connected to pin 5 (GND). I only see things on the stack mode if I have pin 6 connected.

    3. I did not know that, thanks for the clarification.

    I look forward to hearing from you.

    Best regards,

    Lucas Freitas