Analog Devices VISUALDSP++ 3.5, Руководство пользователя

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ADSP-2192 DSP Booting
4-4 Vi+ Loader Manual
for 16-Bit Processors
Once the bus configurations have been determined (assuming that a serial
EEPROM exists), the boot kernel calls a function to commence reading
data from the serial EEPROM. Data format of serial EEPROM boot
stream is described in the
“ADSP-2192 DSP RTBL” on page 4-4 .
Once the kernel has finished reading data from the serial EEPROM, it
proceeds to set up and commit bus configurations for the rest of booting
via the PCI or USB interfaces. For PCI, the configuration registers are set
to be read-only, and the DSP is to respond to PCI requests from the sys-
tem host. For USB, the DSP is to enter an idle loop, allowing the system
host to detect and configure the part.
The final task performed by the kernel after configuring the bus and trans-
ferring control to PCI or USB is to enter an infinite loop, waiting for
instructions. A predefined memory address, DM
0x000000
, is regularly
checked for commands. Once the PCI or USB device has completed boot-
ing the DSP, they can write an instruction to this predefined location and
have the DSP execute any of supported commands.
!
Refer to the datasheet, ADSP-219x/2192 DSP Hardware Reference
and Application Note EE-124 for further details.
ADSP-2192 DSP RTBL
The Vi+ linker produces files with
.DXE
,
.OVL
, and
.SM
exten-
sions. Typically, these file are not shipped with your applications. Instead,
the linker’s output is run through the loader that repackages the linker
output as an
.H
file, which is consumed by an RTBL, as illustrated in
Figure 4-1 . The RTBL output file (
.EXE
) is used by a bootable device (PCI
or USB).
Given that booting from PCI or USB involves code running on the PC
host, you must create a program, which executes on the host, to initiate
and conduct the actual PCI or USB transfer. Because of this, the loader