CS49300 Family DSP
pertinent configuration messages. Writing the
KICKSTART message to the CS493XX begins the
audio decode process. The KICKSTART message
will also be described in the user’s guide for each
application. Until the KICKSTART has been sent,
the decoder is in a wait state.
8. BOOT PROCEDURE & RESET
In this section the process of booting and
downloading to the CS493XX will be covered as
well as how to perform a soft reset. Host boot and
autoboot and reset are covered in this section.
8.1. Host Boot
MNEMONIC
SOFT_RESET
RESERVED
VALUE
A flow diagram of a typical serial download
sequence and a typical parallel download sequence
will be presented, as well as pseudocode
representing a download sequence from the
programmers perspective. The pseudocode is
written in a general sense where function calls are
made to Write_* and Read_*. The * can be
0x000001
0x000002
0x000003
0x000004
0x000005
RESERVED
DOWNLOAD_BOOT
BOOT_SUCCESS_RECEIVED
Table 9. Boot Write Messages
2
replaced by I C or SPI for the serial download
MNEMONIC
BOOT_START
BOOT_SUCCESS
APPLICATION_FAILURE
BOOT_ERROR
INVALID_MSG
VALUE
0x01
0x02
sequence, and INTEL or MOTO for the parallel
download sequence, depending on the mode of host
communication. For each case the general
download algorithm is the same.
0xF0
0xFA
0xFB
0xFC
0xFD
0xFE
0xFF
The download and boot procedure is accomplished
with RESET (pin 36), and the communication pins
discussed in Section 6, “Control” on page 32. The
flow diagrams in Figure 33. Typical Serial Boot
and Download Procedure, and Figure 34. Typical
Parallel Boot and Download Procedure, illustrate
typical boot and download procedures. When
reading in serial mode, you must check that
INTREQ is low to start reading. Similarly, in
parallel mode you must check HOUTRDY.
BOOT_ERROR
INIT_FAILURE
INIT_FAILURE
BAD_CHECKSUM
Table 10. Boot Read Messages
8.1.1. Serial Download Sequence
The following is a detailed description of a serial
download sequence for the CS493XX.
Table 9 defines the boot write messages and
Table 10 defines the boot read messages in mne-
monic and actual hex value. These messages will
be used in the boot sequence.
Note: When reading from the chip in a serial
communication mode, the host must wait for the
interrupt request (INTREQ) to fall before
starting the read cycle.
1) A download sequence is started when the host
Hardware configuration messages are used to
define the behavior of the DSP’s audio ports. A
more detailed description of the different hardware
configurations can be found in the Section 11,
“Hardware Configuration” on page 72.
issues a hard reset and holds the mode pins
appropriately (WR, RD, and PSEL).
2) The host should then send the boot message
DOWNLOAD_BOOT (0x000004). This
causes the CS493XX to initialize itself for
download.
The software configuration messages are specific
to each application. The application code user’s
guide for each application provides a list of all
3) If the initialization was successful the
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