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Rename segment named NMI to LOWCODE

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git-svn-id: svn://svn.cc65.org/cc65/trunk@1571 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz
2002-11-22 00:52:49 +00:00
parent 0cfca414a0
commit 4b8a20fee6
2 changed files with 16 additions and 22 deletions
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22
libsrc/c128/crt0.s
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@@ -24,15 +24,10 @@ IRQInd = $2FD ; JMP $0000 - used as indirect IRQ vector
; ------------------------------------------------------------------------ ; ------------------------------------------------------------------------
; Place the startup code in a special segment to cope with the quirks of ; Place the startup code in a special segment to cope with the quirks of
; c128 banking. Do also create an empty segment named "NMI" to avoid ; c128 banking.
; warnings if the rs232 routines are not used.
.segment "NMI"
; empty
.segment "STARTUP" .segment "STARTUP"
; ------------------------------------------------------------------------
; BASIC header with a SYS call ; BASIC header with a SYS call
.org $1BFF .org $1BFF
@@ -172,13 +167,12 @@ L2: lda zpsave,x
; above will change this setting so that we have RAM from $0000-$BFFF. This ; above will change this setting so that we have RAM from $0000-$BFFF. This
; works quite well with the exception of interrupts: The interrupt handler ; works quite well with the exception of interrupts: The interrupt handler
; is in ROM, and the ROM switches back to the ROM configuration, which means ; is in ROM, and the ROM switches back to the ROM configuration, which means
; that parts of our program may not be accessible. Since the crt0 module is ; that parts of our program may not be accessible. To solve this, we place
; the first module in the program, it will always be below $4000 and always ; the following code into a special segment called "LOWCODE" which will be
; in RAM. So we place several short stubs here that switch back our ROM ; placed just above the startup code, so it goes into a RAM area that is
; config before calling our user defined handlers. These stubs are only ; not banked.
; used if any other code uses the interrupt or break vectors. They are dead
; code otherwise, but since there is no other way to keep them in low memory, .segment "LOWCODE"
; they have to go here.
IRQStub: IRQStub:
cld ; Just to be sure cld ; Just to be sure
@@ -192,7 +186,7 @@ IRQStub:
jsr condes ; Call the functions jsr condes ; Call the functions
pla ; Get old register value pla ; Get old register value
sta MMU_CR sta MMU_CR
jmp IRQInd ; Jump to the save IRQ vector jmp IRQInd ; Jump to the saved IRQ vector
BRKStub: BRKStub:

4
libsrc/c128/rs232.s
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@@ -535,10 +535,10 @@ _rs232_status:
; Because of the C128 banking, the NMI handler must go into the non banked ; Because of the C128 banking, the NMI handler must go into the non banked
; memory, since the ROM NMI entry point will switch to a configuration where ; memory, since the ROM NMI entry point will switch to a configuration where
; only the lowest 16K of RAM are visible. We will place the NMI handler into ; only the lowest 16K of RAM are visible. We will place the NMI handler into
; it's own segment and map this segment into the lower 16K in the linker ; the LOWCODE segment and map this segment into the lower 16K in the linker
; config. ; config.
.segment "NMI" .segment "LOWCODE"
NmiHandler: NmiHandler:
lda #CC65_MMU_CFG ;(2) lda #CC65_MMU_CFG ;(2)