Plit Example; Plit - Summary - Analog Devices VisualDSP++ 3.5 Manual

Memory Overlays and Advanced LDF Commands

PLIT Example

This is an examples of
Simple PLIT – States are Not Saved
A simple PLIT merely copies the symbol's address and overlay ID into
registers and jumps to the overlay manager. The following fragment was
extracted from the global scope (just after the
of
sample fft_group.ldf
either safe or irrelevant.
/* The global PLIT to be used whenever a PROCESSOR or OVERLAY
specific PLIT description is not provided. The plit initializes a
register to the overlay ID and the overlay run-time address of
the symbol called. Ensure the registers used in the plit do not
contain values that cannot be overwritten. */
PLIT
{
P0 = PLIT_SYMBOL_OVERLAYID;
P1.L = PLIT_SYMBOL_ADDRESS;
P1.H = PLIT_SYMBOL_ADDRESS;
JUMP _OverlayManager;
}
As a general rule, minimize overlay transfer traffic. Improve performance
by designing code to ensure overlay functions are imported and use mini-
mal (or no) reloading.
PLIT – Summary
A PLIT is a template of instructions for loading an overlay. For each
overlay routine in the program, the linker builds and stores a list of PLIT
instances according to that template, as it builds its executable. The linker
may also save registers or stack context information. The linker does not
accept a PLIT without arguments.
VisualDSP++ 3.5 Linker and Utilities Manual
for 16-Bit Processors
command implementation.
PLIT{}
. Verify that the contents of
command)
MEMORY{}
and
AX0 AX1
are
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