; Marco van den Heuvel, 2010-01-27
;
- .include "zeropage.inc"
+ .include "zeropage.inc"
- .include "em-kernel.inc"
- .include "em-error.inc"
+ .include "em-kernel.inc"
+ .include "em-error.inc"
- .macpack generic
+ .macpack generic
; ------------------------------------------------------------------------
; Driver signature
- .byte $65, $6d, $64 ; "emd"
- .byte EMD_API_VERSION ; EM API version number
+ .byte $65, $6d, $64 ; "emd"
+ .byte EMD_API_VERSION ; EM API version number
; Jump table.
- .word INSTALL
- .word UNINSTALL
- .word PAGECOUNT
- .word MAP
- .word USE
- .word COMMIT
- .word COPYFROM
- .word COPYTO
+ .word INSTALL
+ .word UNINSTALL
+ .word PAGECOUNT
+ .word MAP
+ .word USE
+ .word COMMIT
+ .word COPYFROM
+ .word COPYTO
; ------------------------------------------------------------------------
; Constants
.bss
-curpage: .res 1 ; Current page number
-window: .res 256 ; Memory "window"
+curpage: .res 1 ; Current page number
+window: .res 256 ; Memory "window"
; Since the functions above are copied to $200, the current contents of this
; memory area must be saved into backup storage. Allocate enough space.
-backup: .res .max (.sizeof (copy), .sizeof (check))
+backup: .res .max (.sizeof (copy), .sizeof (check))
INSTALL:
sei
- jsr backup_and_setup_check_routine
- jsr check::entry
+ jsr backup_and_setup_check_routine
+ jsr check::entry
cli
- ldx #.sizeof (check) - 1
- jsr restore_data
- cpy #$01
- beq @present
- lda #<EM_ERR_NO_DEVICE
- ldx #>EM_ERR_NO_DEVICE
+ ldx #.sizeof (check) - 1
+ jsr restore_data
+ cpy #$01
+ beq @present
+ lda #<EM_ERR_NO_DEVICE
+ ldx #>EM_ERR_NO_DEVICE
rts
@present:
- lda #<EM_ERR_OK
- ldx #>EM_ERR_OK
-; rts ; Run into UNINSTALL instead
+ lda #<EM_ERR_OK
+ ldx #>EM_ERR_OK
+; rts ; Run into UNINSTALL instead
; ------------------------------------------------------------------------
; UNINSTALL routine. Is called before the driver is removed from memory.
;
PAGECOUNT:
- lda #<PAGES
- ldx #>PAGES
+ ldx #>PAGES
rts
; ------------------------------------------------------------------------
MAP:
sei
- sta curpage ; Remember the new page
+ sta curpage ; Remember the new page
clc
- adc #>BASE
- sta ptr1+1
- ldy #0
- sty ptr1
- jsr backup_and_setup_copy_routine
- ldx #<ptr1
+ adc #>BASE
+ sta ptr1+1
+ ldy #0
+ sty ptr1
+ jsr backup_and_setup_copy_routine
stx copy::fetch::address
@L1:
- ldx #$14
- jsr copy::fetch
- ldx ptr1
- sta window,x
- inc ptr1
- bne @L1
+ ldx #$14
+ jsr copy::fetch
+ ldx ptr1
+ sta window,x
+ inc ptr1
+ bne @L1
; Return the memory window
- jsr restore_copy_routine
- lda #<window
- ldx #>window ; Return the window address
+ jsr restore_copy_routine
+ lda #<window
+ ldx #>window ; Return the window address
cli
rts
; ------------------------------------------------------------------------
; USE: Tell the driver that the window is now associated with a given page.
-USE: sta curpage ; Remember the page
- lda #<window
- ldx #>window ; Return the window
+USE: sta curpage ; Remember the page
+ lda #<window
+ ldx #>window ; Return the window
rts
; ------------------------------------------------------------------------
COMMIT:
sei
- lda curpage ; Get the current page
+ lda curpage ; Get the current page
clc
- adc #>BASE
- sta ptr1+1
- ldy #0
- sty ptr1
- jsr backup_and_setup_copy_routine
- ldx #<ptr1
+ adc #>BASE
+ sta ptr1+1
+ ldy #0
+ sty ptr1
+ jsr backup_and_setup_copy_routine
stx copy::stash::address
@L1:
- ldx ptr1
- lda window,x
- ldx #$14
- jsr copy::stash
- inc ptr1
- bne @L1
+ ldx ptr1
+ lda window,x
+ ldx #$14
+ jsr copy::stash
+ inc ptr1
+ bne @L1
; Return the memory window
- jsr restore_copy_routine
+ jsr restore_copy_routine
cli
rts
pha
txa
pha
- jsr backup_and_setup_copy_routine
+ jsr backup_and_setup_copy_routine
pla
tax
pla
- jsr setup
+ jsr setup
; Setup is:
;
; - ptr4 contains the page memory buffer plus offset
; - tmp1 contains zero (to be used for linear memory buffer offset)
- lda #<ptr4
sta copy::fetch::address
- jmp @L3
+ jmp @L3
@L1:
- ldx #$14
- ldy #0
- jsr copy::fetch
- ldy tmp1
- sta (ptr2),y
- inc tmp1
- bne @L2
- inc ptr2+1
+ ldx #$14
+ ldy #0
+ jsr copy::fetch
+ ldy tmp1
+ sta (ptr2),y
+ inc tmp1
+ bne @L2
+ inc ptr2+1
@L2:
- inc ptr4
- beq @L4
+ inc ptr4
+ beq @L4
; Bump count and repeat
@L3:
- inc ptr3
- bne @L1
- inc ptr3+1
- bne @L1
- jsr restore_copy_routine
+ inc ptr3
+ bne @L1
+ inc ptr3+1
+ bne @L1
+ jsr restore_copy_routine
cli
rts
; Bump page register
@L4:
- inc ptr4+1
- jmp @L3
+ inc ptr4+1
+ jmp @L3
; ------------------------------------------------------------------------
; COPYTO: Copy from linear into extended memory. A pointer to a structure
pha
txa
pha
- jsr backup_and_setup_copy_routine
+ jsr backup_and_setup_copy_routine
pla
tax
pla
- jsr setup
+ jsr setup
; Setup is:
;
; - ptr4 contains the page memory buffer plus offset
; - tmp1 contains zero (to be used for linear memory buffer offset)
- lda #<ptr4
sta copy::stash::address
- jmp @L3
+ jmp @L3
@L1:
- ldy tmp1
- lda (ptr2),y
- ldx #$14
- ldy #0
- jsr copy::stash
- inc tmp1
- bne @L2
- inc ptr2+1
+ ldy tmp1
+ lda (ptr2),y
+ ldx #$14
+ ldy #0
+ jsr copy::stash
+ inc tmp1
+ bne @L2
+ inc ptr2+1
@L2:
- inc ptr4
- beq @L4
+ inc ptr4
+ beq @L4
; Bump count and repeat
@L3:
- inc ptr3
- bne @L1
- inc ptr3+1
- bne @L1
- jsr restore_copy_routine
+ inc ptr3
+ bne @L1
+ inc ptr3+1
+ bne @L1
+ jsr restore_copy_routine
cli
rts
; Bump page register
@L4:
- inc ptr4+1
- jmp @L3
+ inc ptr4+1
+ jmp @L3
; ------------------------------------------------------------------------
; Helper function for COPYFROM and COPYTO: Store the pointer to the request
; structure and prepare data for the copy
setup:
- sta ptr1
- stx ptr1+1 ; Save passed pointer
+ sta ptr1
+ stx ptr1+1 ; Save passed pointer
; Get the page number from the struct and adjust it so that it may be used
; with the hardware. That is: ptr4 has the page address and page offset
; tmp2 will hold the bank value
- ldy #EM_COPY::PAGE
- lda (ptr1),y
+ ldy #EM_COPY::PAGE
+ lda (ptr1),y
clc
- adc #>BASE
- sta ptr4+1
+ adc #>BASE
+ sta ptr4+1
; Get the buffer pointer into ptr2
- ldy #EM_COPY::BUF
- lda (ptr1),y
- sta ptr2
+ ldy #EM_COPY::BUF
+ lda (ptr1),y
+ sta ptr2
iny
- lda (ptr1),y
- sta ptr2+1
+ lda (ptr1),y
+ sta ptr2+1
; Get the count, calculate -(count-1) and store it into ptr3
- ldy #EM_COPY::COUNT
- lda (ptr1),y
- eor #$FF
- sta ptr3
+ ldy #EM_COPY::COUNT
+ lda (ptr1),y
+ eor #$FF
+ sta ptr3
iny
- lda (ptr1),y
- eor #$FF
- sta ptr3+1
+ lda (ptr1),y
+ eor #$FF
+ sta ptr3+1
; Get the page offset into ptr4 and clear tmp1
- ldy #EM_COPY::OFFS
- lda (ptr1),y
- sta ptr4
- lda #0
- sta tmp1
+ ldy #EM_COPY::OFFS
+ lda (ptr1),y
+ sta ptr4
+ lda #0
+ sta tmp1
; Done
; Helper routines for copying to and from the +256k ram
backup_and_setup_copy_routine:
- ldx #.sizeof (copy) - 1
+ ldx #.sizeof (copy) - 1
@L1:
- lda copy::entry,x
- sta backup,x
- lda copy::template,x
- sta copy::entry,x
+ lda copy::entry,x
+ sta backup,x
+ lda copy::template,x
+ sta copy::entry,x
dex
- bpl @L1
+ bpl @L1
rts
backup_and_setup_check_routine:
- ldx #.sizeof (check) - 1
+ ldx #.sizeof (check) - 1
@L1:
- lda check::entry,x
- sta backup,x
- lda check::template,x
- sta check::entry,x
+ lda check::entry,x
+ sta backup,x
+ lda check::template,x
+ sta check::entry,x
dex
- bpl @L1
+ bpl @L1
rts
restore_copy_routine:
- ldx #.sizeof (copy) - 1
+ ldx #.sizeof (copy) - 1
restore_data:
- lda backup,x
- sta TARGETLOC,x
+ lda backup,x
+ sta TARGETLOC,x
dex
- bpl restore_data
+ bpl restore_data
rts
projects / cc65 / blobdiff