SLLU349 August   2022

 

  1.   Abstract
  2.   Trademarks
  3. 1Read This First
    1. 1.1 Information About Cautions and Warnings
    2. 1.2 FCC Warning
  4. 2What is in the Box
    1. 2.1 List of Hardware Items for Operation
    2. 2.2 List of Software Items for Operation
  5. 3Summary of Hardware Design
    1. 3.1 Ribbon-Cable Connector J2 and Pinout
    2. 3.2 Configuration of Pullup Resistors for Pins 8, 9, and 10
    3. 3.3 LED Indication of USB Attached
    4. 3.4 Step-by-Step Instructions for Operation and Troubleshooting
  6. 4PMBUS and SMBUS Communications
    1. 4.1 Basic SMBUS Transaction Types Supported
    2. 4.2 Special Signals Used for PMBUS and SMBUS Communications
    3. 4.3 Packet Error Checking (PEC) Implementation
    4. 4.4 Communication Clock Speed and Clock Stretching

4.2 Special Signals Used for PMBUS and SMBUS Communications

Refer to Table 3-2 for special signal lines used for PMBUS and SMBUS communications.

Specifically, a target device can assert an ALERT signal (by pulling it low) to report a fault or a warning condition to the USB Interface Adapter; the host PC can obtain the ALERT signal by polling the USB Interface Adapter. Note that the USB Interface Adapter does not support any Host Notify Protocol, which means that the USB Interface Adapter cannot become a PMBUS or SMBUS target and, therefore, cannot support a target to temporarily become a host and notify the host about the fault or the warning condition.

For PMBUS communications, the USB Interface Adapter provides five CONTROL signals, each of which can be used to enable or disable the powering up of one or multiple targeted device or devices.

Write Protect signal is not supported; neither is the RESET signal.