Echelon Neuron C - Manual (Page 244)

232 Neuron C Custom System Images
1 Run the stand-alone Neuron linker as described in Appendix A. In
addition to the linker switches described in Appendix A, several other
switches, specific to custom system image creation, are required as
follows.
• Specify the -c switch. This must be the first switch that you
specify to the linker. There are no arguments associated with the
-c switch.
• Specify the base system image with the -b switch. The -b switch
must be followed by the filename or pathname of the base image
(without a filename extension). Start with the Sys3150 system
image or a custom system image based on the Sys3150 system
image. For example, to use the standard version 13 system image
for Neuron 3150 Chip-based custom devices, the switch would be
as follows:
-b \LonWorks\Images\Ver13\SYS3150
• A custom system image can only use ROM and a limited amount
of far onchip RAM. Thus, the only memory map switch that is
needed for custom system image construction is the -Z switch.
When the linker is constructing a custom system image, the -Z
switch specifies the end of the reserved ROM for the custom
system image. The base image already reserves some amount of
ROM from address 0x0000 to some value x (for a standard system
image, x is 0x3FFF).
The -Z switch followed by some value yp reserves the ROM area
from x+1 to y for the custom system image being created. Thus,
yp is the page number corresponding to the address y . For
example, to reserve from 0x4000 to 0x4FFF for the custom system
image being constructed, the value for the -Z switch would be
"4F." The reserved area must at least be large enough to contain
the object files being included. The minimum value for the -Z
switch is "40," which would be just one page (256 bytes)
additional ROM space beyond the standard system image. This
custom system image would end at 0x40FF.
Any additional unused space in the new reserved area is kept for
later use by future versions of this particular custom system
image. The new reserved amount of ROM is automatically made
known to the linker when it uses the custom system image in
linking a Neuron C application program at some later time, and
the application program is then permitted to use only any
remaining unreserved ROM.
• Specify the -V switch to assign a version number to the custom
system image, within the range 128..255. Follow the -V switch
with the desired version number, in decimal. Move custom
system image files to the VER nnn subdirectory in the IMAGES
directory that corresponds to the version number chosen. If the
appropriate VER
nnn directory does not exist, create one.
The following example creates a custom system image from the SYS3150
standard system image and the object files named in the Objs.lst script