ADAU1781

This evaluation board provides full access to all analog and digital I/Os on the ADAU1781. The SigmaDSP is controlled by Analog Devices, Inc., SigmaStudio™ software, which interfaces to the board via a USB connection. This evaluation board can be powered either over the USB bus or by a single 3.8 V to 6 V supply, which is regulated to the voltages required on the board. The PC board is a 4-layer design, with a single ground plane and a single power plane on the inner layers. The board contains onboard microphones and speaker, and connectors for external microphones and speaker. The master clock can be provided externally or by the on-board 12.288 MHz active oscillator.

The Analog Devices USBi “USB Interface” (EVAL-ADUSB2EBZ) board is the interface between your PC's USB port and SigmaDSP hardware's data input pins. This interface can be used with any evaluation board which includes an External SPI/I²C header (Aardvark Header). The EVAL-ADUSB2EBZ board is capable of both SPI and I²C communication (which is user selectable) and can supply IOVDD of either 3.3V or 1.8V.The USBi interface is powered from the computer's USB port.

Using USBi in SigmaStudio:

To communication between SigmaStudio and the USBi board, a communication channel block must be added to the Schematic design. To locate the block, select the Hardware Configuration Tab, in the ToolBox or Tree ToolBox window choose the “Communication Channels” category, and select the USBi block.

This block provides connections for multiple processors (ICs / DSPs), allowing you to use multiple processors in a single design. This block allows you to explicitly specify both the communication protocol (SPI or I²C) and the part's address, I²C address or SPI catch line. The DSP hardware's address must match the block's selected address for communication to function properly. See the parts data sheet for more information about addressing (e.g. ADR_SEL, ADDR0, or ADDR1 pins). The default USBi protocol is I²C, to enable SPI, you must first select an SPI address in the block's drop down menu and then perform three write operations (e.g. press the write button the Register Read/Write Window 3 times). The USBi hardware has LEDs which indicate the current mode, I²C or SPI.