AR# 37561: Xilinx Evaluation Kits - How do I interface with the UCD9240 controller on my board?
Xilinx Evaluation Kits - How do I interface with the UCD9240 controller on my board?
Xilinx Evaluation Kits (such as the ML605 or KC705) leverage the UCD9240 PMBus controller.
How do I interface with and read measurements from the UCD9240 controller?
There are two approaches which can be followed:
Texas instruments (TI) provide the Fusion Digital Power Designer software package (http://focus.ti.com/docs/toolsw/folders/print/fusion_digital_power_designer.html) which includes several tools that are capable of communicating with the UCD92xx series of controllers from a Windows-based host computer. It requires the use of a USB Interface Adapter EVM (http://focus.ti.com/docs/toolsw/folders/print/usb-to-gpio.html) to connect between the PMBus (I2C) interface of the UCD92xx controller and the USB port on the host computer. The software is designed to interface with the UCD9240 controllers through this device only. 6 and 7 Series Evaluation Kits are shipped with a TI flyer which contains information that allows you to purchase this EVM at a discount. These Evaluation Kits are built with an on-board connector which is wired for the TI EVM interface and provides access to the PMBus and UCD9240 for monitoring purposes.
Another more complicated method to access the PMBus (I2C) interface is available on the ML605 and SP605. The FPGA on these boards is directly connected to the UCD9240s PMBus (I2C) interface through level shifters. This provides the means to self monitor the power rails over the PMBus (I2C) interface, but requires custom code creation on yout part in order for the Xilinx FPGA to read and write properly formatted PMBus and UCD9240 commands. TI recommends that you reference their UCD92xx PMBus Command Reference Manual (http://focus.ti.com/lit/ug/sluu337/sluu337.pdf) along with the industry standard PMBus Specification (http://pmbus.org/specs.html) for UCD9240 command codes, data formatting, and PMBus protocol.
In extreme scenarios, the TI Fusion Digital Power Manufacturing Tool and TI EVM can also be used to reset the power controller to their factory settings using the appropriate XML files.