ADAV4601 System Design Document
Confidential Information
Rev.1 August 2009
Analog Devices
Page 50
SECTION 6 – THE APPLICATION LAYER CREATION SOFTWARE
THE APPLICATION LAYER
The purpose of the Application Layer is to simplify system design and reduce time to market. It achieves this by
drastically reducing I
2
C writes while still maintaining full control over a customised audio flow in the ADAV4601.
What this means to the user is the chance to have complicated functions in the audio flow and yet simple register
writes to control these functions. This will drastically simplify the microcontroller code for the user and also means
that the I
2
C bus will not be “clogged” with unnecessary writes.
Physically the Application Layer is a hardware module on-chip that interprets the output from the Application Layer
Creation Software and allows the control described above.
APPLICATION LAYER CREATION SOFTWARE
The aim of the Application Layer Creation Software is to create an upper layer of registers, simpler than the register
map created by SigmaStudio. Once a project is finished in SigmaStudio, it gives a full register map to control every
block in the project. The blocks are controlled by the SigmaDSP parameters, in the Parameter RAM. Dealing with
this is usually too complex and not easily readable. Here is where the Application Layer deals with this complexity,
offering a simple custom register map that will perform all the complex operations needed. All the reads and writes
are done through the I
2
C bus. See Figure 38.
Program
ROM
Program
RAM
SigamDSP
(MAC)
Parameter
RAM
DATA
RAM
Parameter
ROM
I2C Writer
Application
Layer
Figure 38. ADAV4601 Hardware Block Diagram
In order to define the Application Layer, the Application Layer Creation Software can import any SigmaStudio flow,
detect the blocks present in the project, and then the user can define a custom register map for them. Once this is
done, the software can compile the code and create the Application Layer ROMs. These ROMs can be downloaded
directly to the Application Layer RAM from the software provided (SigmaStudio), and in a system design can be
booted an external I
2
C EEPROM memory.
In addition to the ROMs, the Application Layer Creation software will produce:
•
HTML Register map documentation. Useful to know how to control the register map that has been
created.
•
Standard ‘C’ code library. Ready to be embedded in any system with an I
2
C master controller, facilitating
the control (read and write) of the registers present in the map. ‘C’ functions for every field, in every
register, are produced.
