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Added docs to set_irq / reset_irq.

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git-svn-id: svn://svn.cc65.org/cc65/trunk@5415 b7a2c559-68d2-44c3-8de9-860c34a00d81
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ol.sc 2012-01-21 12:28:23 +00:00
parent 631c553233
commit 7103aa04ae
2 changed files with 55 additions and 2 deletions
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53
doc/funcref.sgml
View File

@ -58,7 +58,9 @@ function.
<item><ref id="_sys" name="_sys">
<item><ref id="getcpu" name="getcpu">
<item><ref id="reset_brk" name="reset_brk">
<item><ref id="reset_irq" name="reset_irq">
<item><ref id="set_brk" name="set_brk">
<item><ref id="set_irq" name="set_irq">
</itemize>
@ -4119,6 +4121,22 @@ the program ends.
</quote>
<sect1>reset_irq<label id="reset_irq"><p>
<quote>
<descrip>
<tag/Function/Resets the C level interrupt request vector.
<tag/Header/<tt/<ref id="6502.h" name="6502.h">/
<tag/Declaration/<tt/void reset_irq (void);/
<tag/Description/<tt/reset_irq/ resets the C level interrupt request vector.
<tag/Availability/cc65
<tag/See also/
<ref id="set_irq" name="set_irq">
<tag/Example/None.
</descrip>
</quote>
<sect1>revers<label id="revers"><p>
<quote>
@ -4452,6 +4470,41 @@ the program terminates.
</quote>
<sect1>set_irq<label id="set_irq"><p>
<quote>
<descrip>
<tag/Function/Set the C level interrupt request vector to the given address.
<tag/Header/<tt/<ref id="6502.h" name="6502.h">/
<tag/Declaration/<tt/void __fastcall__ set_irq (irq_handler f, void *stack_addr, size_t stack_size);/
<tag/Description/<tt/set_irq/ allows a user program to handle interrupt requests
(IRQs) within the program code by letting the vector point to a user written C
function. The runtime library installs a small stub that saves the zero page
registers used by the C runtime before calling the handler function and restores
them after the handler function returns. Additionally the stub temporarily switches
the C runtime stack to the stack area provided as parameter. If the handler function
was set up to handle a "private", "exclusive" interrupt request source it must
return the value <tt/IRQ_HANDLED/ if and only if it has verified that the current
interrupt request actually stems from that source. In all other cases it must return
the value <tt/IRQ_NOT_HANDLED/.
<tag/Limits/
<itemize>
<item>The function is only available as fastcall function, so it may only
be used in presence of a prototype.
<item>The stub saves the zero page registers used by the C runtime and switches
to the provided stack area. This means that it is safe to execute C code,
even if C code was interrupted. Be careful however not to call into the C library,
and do not enable stack checks for the handler function or any other function called
from it.
</itemize>
<tag/Availability/cc65
<tag/See also/
<ref id="reset_irq" name="reset_irq">
<tag/Example/None.
</descrip>
</quote>
<sect1>setjmp<label id="setjmp"><p>
<quote>

4
libsrc/common/interrupt.s
View File

@ -1,4 +1,4 @@
;
;
; Oliver Schmidt, 2012-01-18
;
; void __fastcall__ set_irq (irq_handler f, void *stack_addr, size_t stack_size);
@ -53,7 +53,7 @@
.proc clevel_irq
; Is C level interrupt request vector set?
lda irqvec+2 ; High byte is enough
lda irqvec+2 ; High byte is enough
bne @L1
clc ; Interrupt not handled
rts