Renesas 70 5.2.4 Writing Cyclic Handler/Alarm Handler

Chapter 5 Detailed Applications
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5.2.4 Writing Cyclic Handler/Alarm Handler
When describing the cyclic or alarm handler in Assembly Language, observe the following precautions.
1. At the beginning of file, be sure to include "mr308.inc" which is in the system directory.
2. For the symbol indicating the handler start address, make the external declaration.55
3. Always use the RTS instruction (subroutine return instruction) to return from cyclic han-
dlers and alarm handlers.
For examples:
.INCLUDE mr308.inc ----- (1)
.GLB cychand ----- (2)
cychand: :
; handler process
:
rts ----- (3)
Figure 5.10 Example Handler Written in Assembly Language
55 Use the .GLB pseudo-directive.