Enriching Boot Eproms With No-Boot Data - Analog Devices VisualDSP++ 3.5 Manual

ADSP-219x DSP Booting
789ABC
DEF012
345678
9ABCDE
F01234
56789A
BCDEF0 // 8th (last) data word optional,
// controlled by the -checksum switch

Enriching Boot EPROMs with No-boot Data

The loader's splitter functionality (refer to
enables powerful memory utilization in combination with the parallel
EPROM boot mode. The same EPROM used for booting can also be used
at runtime for read-only data and overlay storage. Furthermore, the DSP
can execute non-speed-critical parts of the program directly from the
EPROM, whereas real-time algorithms have been booted into on-chip
memory.
When invoked with the
cesses all kinds of LDF segments.
loader's boot stream generator, and
splitter. Boot stream and splitter data can be combined within a single
EPROM image.
Assuming a cost-sensitive application comprising an ADSP-2196 DSP and
a 64-Kbyte EPROM, the boot stream probably does not exceed
40 kilobytes (8K x 3 bytes + 8K x 2 bytes) of length. The rest of the
EPROM can be used to store different sets of coefficients and the slow ini-
tialization and control code. A reasonable organization of the 8-bit
EPROM is described in
Since the DSP cannot access off-chip memories with addresses lower than
, it needs to access segments
0x010000
hrough alias windows. If only address lines A0 through A15 are con-
t
nected, address
seg_ext_data
3-16
-readall
Table 3-4.
aliases to any
0x00 A000
stores 16-bit data. Thus, its physical addresses must be
"No-booting" on page
switch (on page 3-23), the loader pro-
segments are passed to the
TYPE(RAM)
segments are passed to its
TYPE(ROM)
seg_ext_data
address. Segment
0x00 A000
VisualDSP++ Loader Manual
3-12)
and se
g_ext_code
for 16-Bit Processors