CS49300 Family DSP
CS493XX sends out the boot message
BOOT_START (0x01) and the host should
proceed to step 5.
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.
4) If initialization fails, the CS493XX sends out
an INIT_FAILURE boot message byte (0xFD
or 0xFE), INVALID_MSG byte (0xFB), or
BOOT_ERROR byte (0xFA or 0xFC) and
spins waiting for a hard reset. The host should
re-try steps 1 through 3 and if failure is met
again, the serial communication timing and
protocol should be inspected.
3) If the initialization was successful the
CS493XX sends out the boot message
BOOT_START (0x01) and the host should
proceed to step 5.
4) If initialization fails, the CS493XX sends out
an INIT_FAILURE boot message byte (0xFD
or 0xFE), INVALID_MSG byte (0xFB), or
BOOT_ERROR byte (0xFA or 0xFC) and
spins waiting for a hard reset. The host should
re-try steps 1 through 3 and if failure is met
again, the serial communication timing and
protocol should be inspected.
5) After receiving the BOOT_START byte, the
host should write the downloadable image
(from the .LD file).
6) The end of the .LD file contains a three byte
checksum. If the checksum is good after
download, the CS493XX will send a
BOOT_SUCCESS message (0x02) to the host.
If the checksum was bad, the CS493XX
responds with the BAD_CHECKSUM
message byte (0xFF) and spins, waiting for
hard reset.
5) After receiving the BOOT_START byte, the
host should write the downloadable image
(from the .LD file).
6) The end of the .LD file contains a three byte
checksum. If the checksum is good after
download, the CS493XX will send a
BOOT_SUCCESS message (0x02) to the host.
If the checksum was bad, the CS493XX
responds with the BAD_CHECKSUM
message byte (0xFF) and spins, waiting for
hard reset.
7) After reading out the BOOT_SUCCESS byte,
the
host
should
send
the
BOOT_SUCCESS_RECEIVED
message
(0x000005) which will cause an internal
application code reset and allow the
downloaded application to run.
8) After waiting 5ms to allow the downloaded
application to initialize, the host can send
configuration messages for both hardware and
software configuration.
7) After reading out the BOOT_SUCCESS byte,
the
host
should
send
the
BOOT_SUCCESS_RECEIVED
message
(0x000005) which will cause an internal
application code reset and allow the
downloaded application to run.
8.1.2. Parallel Download Sequence
The following is a detailed description of a parallel
download sequence for the CS493XX.
8) After waiting 5ms to allow the downloaded
application to initialize, the host can send
configuration messages for both hardware and
software configuration.
Note: When reading from the chip in a parallel
communication mode, the host must read the
HOSTCTL register and test the HOUTRDY bit
before starting the read cycle.
1) A download sequence is started when the host
DS339PP4
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