Keil RTX51, Руководство пользователя

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RTX Tiny 23
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Compiling RTX51 Tiny Programs
RTX51 Tiny applications require no special compiler switches or settings. You should be
able to compile your RTX51 Tiny source files just as you would ordinary C source files.
Linking RTX51 Tiny Programs
RTX51 Tiny applications must be linked using the BL51 code banking linker/locator.
The
RTX51TINY directive must be specified on the command line after all object files.
Refer to the RTX51TINY directive in Utilities manual.
Optimizing RTX51 Tiny Programs
The following items should be noted when creating RTX51 applications.
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If possible, disable round-robin multitasking. Tasks which use round-robin multi-
tasking require 13 bytes of stack space to store the task context (registers, etc.). This
context storage is not required if task switching is triggered by the
os_wait function.
The os_wait function also produces an improved system reaction time since a task
which is waiting for execution does not have to wait for the entire duration of the
round-robin time-out.
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Do not set the timer tick interrupt rate too fast. Setting the tick rate to a low number
increases the number of timer ticks per second. There is about 100 to 200 CPU cy-
cles of overhead for each timer tick interrupt. Therefore, the timer tick rate should be
set high enough to minimize interrupt latency.