Cirrus Logic AN298 User Manual
Cirrus Logic Hardware

Copyright
Cirrus Logic, Inc. 2013
(All Rights Reserved)
CS485xx Firmware User’s Manual:
General Overview and Common Firmware Modules
Contents
Document Strategy
Overview
Firmware Messaging
OS Firmware Module
Audio Manager Firmware Module
PCM Firmware Module
Low Power Mode
Watchdog Timer
Document Revisions
Overview
AN298 provides a description of the operation of firmware
for the CS485xx family of DSPs. This document gives a
general overview to the family of CS485xx Firmware
User’s Manuals designated by the general name
AN298[X][Y]; where [X] = MPM (Matrix Processing
Module), VPM (Virtual Processing Module), PPM (Post
Processing Module), and [Y] = A,B,C, etc. Note that the
CS485xx family of DSPs does not contain a compressed
data decoder.
More specifically, the purpose of this document is to serve
as an introduction to the various DSP Firmware designed
specifically to run on the CS485xx DSP. This document will
attempt to explain frequently used terminology and, at the
same time, systematically explain the OS operation and
communication for the CS485xx.
CS485xx Block Diagram
Mid-Processor Overlay
PCM Outputs
Post-Processor Overlay (with APP loaded)
ID = 0x83
ID = 0xD9
ID = 0xD5
ID = 0xD4
Tone
Control
Module
Re-Eq
Module
Bass
Management
Module
Parametric
EQ
Module
Delay
Module
Audio Manager
Module
Includes:
Gain (master)
Mute (master)
Channel Trim
Channel Remap
Up-sampler
Mid-Processor Module
e.g. PLII, PLIIx, Neo6, Crossbar,
Viva+, COMS2, Neural Surround,
Circle Surround 2
Virtualizer-Processor
Module
e.g. DVS2, DH2, SRS TSXT,
Audistry
Virtualizer -Processor Overlay
Mid-Processor Overlay
PCM inputs
Down-
sampler
AN298
AN298RC14
MAR '13