; Ullrich von Bassewitz, 2002-12-02
;
- .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 DEINSTALL
- .word PAGECOUNT
- .word MAP
- .word USE
- .word COMMIT
- .word COPYFROM
- .word COPYTO
+ .word INSTALL
+ .word DEINSTALL
+ .word PAGECOUNT
+ .word MAP
+ .word USE
+ .word COMMIT
+ .word COPYFROM
+ .word COPYTO
; ------------------------------------------------------------------------
; Constants
banks: .byte $E3,$E7,$EB,$EF ; 130XE banks for cpu banking
stacktest: sei
- ldy banks
- sty $D301
- tax ; A is set by caller
- inx
- stx $4000 ; change $4000
- ldy #$FF ; STACK+13
- sty $D301
- cmp $4000 ; changed?
- beq @1
- sec ; error
- bcs @2
+ ldy banks
+ sty $D301
+ tax ; A is set by caller
+ inx
+ stx $4000 ; change $4000
+ ldy #$FF ; STACK+13
+ sty $D301
+ cmp $4000 ; changed?
+ beq @1
+ sec ; error
+ bcs @2
@1: clc
@2: sta $4000 ; restore
- cli
- rts
+ cli
+ rts
stacktest_end:
stackcopy: sei ; disable interrupts
@1: dex ; pre-decrement (full page x=0)
- ldy #$FF ; this will be replaced STACK+3
- sty $D301 ; set bank
- lda $FF00,x ; address to copy from STACK+8,+9
- ldy #$FF ; this will be replaced STACK+11
- sty $D301
- sta $FF00,x ; address to copy to STACK+16,+17
- cpx #0
- bne @1
- ldy #$FF ; portb_save STACK+23
- sty $D301
- cli ; enable interrupts
- rts
+ ldy #$FF ; this will be replaced STACK+3
+ sty $D301 ; set bank
+ lda $FF00,x ; address to copy from STACK+8,+9
+ ldy #$FF ; this will be replaced STACK+11
+ sty $D301
+ sta $FF00,x ; address to copy to STACK+16,+17
+ cpx #0
+ bne @1
+ ldy #$FF ; portb_save STACK+23
+ sty $D301
+ cli ; enable interrupts
+ rts
stackcopy_end:
stackcopy_byte: sei
- ldy #$FF ; STACK+2
- sty $D301
- lda $FFFF ; STACK+7 +8
- ldy #$FF ; STACK+10
- sty $D301
- sta $FFFF ; STACK+15 +16
- ldy #$FF ; STACK+18
- sty $D301
- cli
- rts
+ ldy #$FF ; STACK+2
+ sty $D301
+ lda $FFFF ; STACK+7 +8
+ ldy #$FF ; STACK+10
+ sty $D301
+ sta $FFFF ; STACK+15 +16
+ ldy #$FF ; STACK+18
+ sty $D301
+ cli
+ rts
stackcopy_byte_end:
.code
install_transfer:
- ldx #stackcopy_end - stackcopy - 1
+ ldx #stackcopy_end - stackcopy - 1
@1: lda stackcopy,x
- sta STACK,x
- dex
- bpl @1
- rts
+ sta STACK,x
+ dex
+ bpl @1
+ rts
install_byte_transfer:
- ldx #stackcopy_byte_end - stackcopy_byte - 1
+ ldx #stackcopy_byte_end - stackcopy_byte - 1
@2: lda stackcopy_byte,x
- sta STACK,x
- dex
- bpl @2
- rts
+ sta STACK,x
+ dex
+ bpl @2
+ rts
install_test:
- ldx #stacktest_end - stacktest - 1
+ ldx #stacktest_end - stacktest - 1
@3: lda stacktest,x
- sta STACK,x
- dex
- bpl @3
- rts
+ sta STACK,x
+ dex
+ bpl @3
+ rts
setpage:
- tax ; save page
- and #$C0 ; mask out bank
- clc
- ror
- ror ; divide by 64
- ror ; 64 pages in each bank
- ror
- ror
- ror
- sta curbank ; Remember the new bank
- txa ; bring back page
- and #$3F ; mask out page
- sta curpage ; curpage in bank
- rts
+ tax ; save page
+ and #$C0 ; mask out bank
+ clc
+ ror
+ ror ; divide by 64
+ ror ; 64 pages in each bank
+ ror
+ ror
+ ror
+ sta curbank ; Remember the new bank
+ txa ; bring back page
+ and #$3F ; mask out page
+ sta curpage ; curpage in bank
+ rts
; ------------------------------------------------------------------------
;
INSTALL:
- lda $D301 ; save state of portb
- sta portb_save
- tay
-
- jsr install_test ; doesn't touch Y
- sty STACK+13
-
- lda $4000 ; test for extended memory
- jsr STACK
- bcs @1
- lda #EM_ERR_OK
- rts
+ lda $D301 ; save state of portb
+ sta portb_save
+ tay
+
+ jsr install_test ; doesn't touch Y
+ sty STACK+13
+
+ lda $4000 ; test for extended memory
+ jsr STACK
+ bcs @1
+ lda #EM_ERR_OK
+ rts
@1: lda #EM_ERR_NO_DEVICE
- rts
+ rts
; ------------------------------------------------------------------------
; DEINSTALL routine. Is called before the driver is removed from memory.
;
DEINSTALL:
- rts
+ rts
; ------------------------------------------------------------------------
;
PAGECOUNT:
- lda #<PAGES
- ldx #>PAGES
- rts
+ ldx #>PAGES
+ rts
; ------------------------------------------------------------------------
; MAP: Map the page in a/x into memory and return a pointer to the page in
;
MAP: jsr setpage ; extract the bank/page
- add #>BANK ; $4000 + page (carry is cleared)
- sta ptr1+1
- ;ldy #$00
- ;sty ptr1
+ add #>BANK ; $4000 + page (carry is cleared)
+ sta ptr1+1
+ ;ldy #$00
+ ;sty ptr1
- lda #<window
- sta ptr2
- lda #>window
- sta ptr2+1
+ lda #<window
+ sta ptr2
+ lda #>window
+ sta ptr2+1
; Transfer one page
- jsr install_transfer ; Transfer one page
+ jsr install_transfer ; Transfer one page
- ldx curbank
- lda banks,x
- sta STACK+3 ; set bank to copy from
+ ldx curbank
+ lda banks,x
+ sta STACK+3 ; set bank to copy from
; lda ptr1
; sta STACK+8
- lda ptr1+1
- sta STACK+9 ; set copy from address
- lda portb_save
- sta STACK+11 ; set portb restore
- sta STACK+23 ; set final portb restore
- lda ptr2
- sta STACK+16
- lda ptr2+1
- sta STACK+17 ; set copy to address
-
- ldx #0 ; full page copy
- jsr STACK ; do the copy!
+ lda ptr1+1
+ sta STACK+9 ; set copy from address
+ lda portb_save
+ sta STACK+11 ; set portb restore
+ sta STACK+23 ; set final portb restore
+ lda ptr2
+ sta STACK+16
+ lda ptr2+1
+ sta STACK+17 ; set copy to address
+
+ ldx #0 ; full page copy
+ jsr STACK ; do the copy!
; Return the memory window
- lda #<window
- ldx #>window ; Return the window address
+ lda #<window
+ ldx #>window ; Return the window address
- rts
+ rts
; ------------------------------------------------------------------------
; USE: Tell the driver that the window is now associated with a given page.
USE: ;sta curpage ; Remember the page
- jsr setpage ; extract bank/page
- lda #<window
- ldx #>window ; Return the window
- rts
+ jsr setpage ; extract bank/page
+ lda #<window
+ ldx #>window ; Return the window
+ rts
; ------------------------------------------------------------------------
; COMMIT: Commit changes in the memory window to extended storage.
COMMIT: lda curpage ; Get the current page
- cmp #$FF
- beq commit_done ; Jump if no page mapped
+ cmp #$FF
+ beq commit_done ; Jump if no page mapped
- clc
- add #>BANK
- sta ptr2+1
- ;ldy #$00
- ;sty ptr2
+ clc
+ add #>BANK
+ sta ptr2+1
+ ;ldy #$00
+ ;sty ptr2
- lda #<window
- sta ptr1
- lda #>window
- sta ptr1+1
+ lda #<window
+ sta ptr1
+ lda #>window
+ sta ptr1+1
; Transfer one page/all bytes
- jsr install_transfer ; Transfer one page
-
- lda portb_save
- sta STACK+3 ; set bank to copy from
- sta STACK+23 ; set final portb restore
- lda ptr1
- sta STACK+8
- lda ptr1+1
- sta STACK+9 ; set copy from address
- ldx curbank
- lda banks,x
- sta STACK+11 ; set bank to copy to
- ;lda ptr2
- ;sta STACK+16
- lda ptr2+1
- sta STACK+17 ; set copy to address
-
- ldx #0 ; full page copy
- jsr STACK ; do the copy!
+ jsr install_transfer ; Transfer one page
+
+ lda portb_save
+ sta STACK+3 ; set bank to copy from
+ sta STACK+23 ; set final portb restore
+ lda ptr1
+ sta STACK+8
+ lda ptr1+1
+ sta STACK+9 ; set copy from address
+ ldx curbank
+ lda banks,x
+ sta STACK+11 ; set bank to copy to
+ ;lda ptr2
+ ;sta STACK+16
+ lda ptr2+1
+ sta STACK+17 ; set copy to address
+
+ ldx #0 ; full page copy
+ jsr STACK ; do the copy!
commit_done:
- rts
+ rts
; ------------------------------------------------------------------------
; The function must not return anything.
;
COPYFROM:
- sta ptr3
- stx ptr3+1 ; Save the passed em_copy pointer
-
- jsr install_byte_transfer ; install the stack copy routine
-
- ldy #EM_COPY::OFFS
- lda (ptr3),y
- sta STACK+7 ; offset goes into BANK low
-
- ldy #EM_COPY::PAGE
- lda (ptr3),y
- sta tmp1 ; save page for later
- ;add #>BANK
- ;sta STACK+8 ; BANK + page goes into BANK high
-
- ldy #EM_COPY::BUF
- lda (ptr3),y
- sta STACK+15 ; buffer goes into dest low
- iny
- lda (ptr3),y
- sta STACK+16 ; buffer goes into dest high
-
- ldy #EM_COPY::COUNT
- lda (ptr3),y ; Get bytes in last page
- sta ptr4
- iny
- lda (ptr3),y ; Get number of pages
- sta ptr4+1
-
- lda tmp1 ; extract bank/page
- jsr setpage ; sets curbank/curpage
- lda curpage
- add #>BANK ; add to BANK address
- sta STACK+8 ; current page in bank
- ldx curbank
- lda banks,x
- sta STACK+2 ; set bank in stack
- lda portb_save
- sta STACK+10 ; set bank restore in stack
- sta STACK+18 ; set final restore too
+ sta ptr3
+ stx ptr3+1 ; Save the passed em_copy pointer
+
+ jsr install_byte_transfer ; install the stack copy routine
+
+ ldy #EM_COPY::OFFS
+ lda (ptr3),y
+ sta STACK+7 ; offset goes into BANK low
+
+ ldy #EM_COPY::PAGE
+ lda (ptr3),y
+ sta tmp1 ; save page for later
+ ;add #>BANK
+ ;sta STACK+8 ; BANK + page goes into BANK high
+
+ ldy #EM_COPY::BUF
+ lda (ptr3),y
+ sta STACK+15 ; buffer goes into dest low
+ iny
+ lda (ptr3),y
+ sta STACK+16 ; buffer goes into dest high
+
+ ldy #EM_COPY::COUNT
+ lda (ptr3),y ; Get bytes in last page
+ sta ptr4
+ iny
+ lda (ptr3),y ; Get number of pages
+ sta ptr4+1
+
+ lda tmp1 ; extract bank/page
+ jsr setpage ; sets curbank/curpage
+ lda curpage
+ add #>BANK ; add to BANK address
+ sta STACK+8 ; current page in bank
+ ldx curbank
+ lda banks,x
+ sta STACK+2 ; set bank in stack
+ lda portb_save
+ sta STACK+10 ; set bank restore in stack
+ sta STACK+18 ; set final restore too
copyfrom_copy:
- lda ptr4 ; check if count is zero
- bne @4
- lda ptr4+1
- beq done
+ lda ptr4 ; check if count is zero
+ bne @4
+ lda ptr4+1
+ beq done
@4: jsr STACK ; copy one byte
- sec
- lda ptr4
- sub #1
- sta ptr4
- bcs @1
- lda ptr4+1
- beq @1
- sub #1
- sta ptr4+1
+ sec
+ lda ptr4
+ sub #1
+ sta ptr4
+ bcs @1
+ lda ptr4+1
+ beq @1
+ sub #1
+ sta ptr4+1
@1: inc STACK+7 ; increment address in BANK
- bne @2
- inc STACK+8
- lda STACK+8
- cmp #$80 ; we stepped outside bank
- bne @2
-
- inc curbank ; get next bank
- ldx curbank
- lda banks,x
- sta STACK+2 ; set new bank
- lda #$40 ; set address back to $4000
- sta STACK+8
+ bne @2
+ inc STACK+8
+ lda STACK+8
+ cmp #$80 ; we stepped outside bank
+ bne @2
+
+ inc curbank ; get next bank
+ ldx curbank
+ lda banks,x
+ sta STACK+2 ; set new bank
+ lda #$40 ; set address back to $4000
+ sta STACK+8
@2: inc STACK+15 ; increment buffer address
- bne @3
- inc STACK+16
+ bne @3
+ inc STACK+16
@3: jmp copyfrom_copy ; copy another byte
done:
- rts
+ rts
; ------------------------------------------------------------------------
; COPYTO: Copy from linear into extended memory. A pointer to a structure
;
COPYTO:
- sta ptr3
- stx ptr3+1 ; Save the passed em_copy pointer
-
- jsr install_byte_transfer ; install the stack copy routine
-
- ldy #EM_COPY::OFFS
- lda (ptr3),y
- sta STACK+15 ; offset goes into BANK low
-
- ldy #EM_COPY::PAGE
- lda (ptr3),y
- sta tmp1 ; save page for later
- ;add #>BANK
- ;sta STACK+16 ; BANK + page goes into BANK high
-
- ldy #EM_COPY::BUF
- lda (ptr3),y
- sta STACK+7 ; buffer goes into dest low
- iny
- lda (ptr3),y
- sta STACK+8 ; buffer goes into dest high
-
- ldy #EM_COPY::COUNT
- lda (ptr3),y ; Get bytes in last page
- sta ptr4
- iny
- lda (ptr3),y ; Get number of pages
- sta ptr4+1
-
- lda tmp1 ; extract bank/page
- jsr setpage ; sets curbank/curpage
- lda curpage
- add #>BANK ; add to BANK address
- sta STACK+16 ; current page in bank
- ldx curbank
- lda banks,x
- sta STACK+10 ; set bank in stack
- lda portb_save
- sta STACK+2 ; set bank restore in stack
- sta STACK+18 ; set final restore too
+ sta ptr3
+ stx ptr3+1 ; Save the passed em_copy pointer
+
+ jsr install_byte_transfer ; install the stack copy routine
+
+ ldy #EM_COPY::OFFS
+ lda (ptr3),y
+ sta STACK+15 ; offset goes into BANK low
+
+ ldy #EM_COPY::PAGE
+ lda (ptr3),y
+ sta tmp1 ; save page for later
+ ;add #>BANK
+ ;sta STACK+16 ; BANK + page goes into BANK high
+
+ ldy #EM_COPY::BUF
+ lda (ptr3),y
+ sta STACK+7 ; buffer goes into dest low
+ iny
+ lda (ptr3),y
+ sta STACK+8 ; buffer goes into dest high
+
+ ldy #EM_COPY::COUNT
+ lda (ptr3),y ; Get bytes in last page
+ sta ptr4
+ iny
+ lda (ptr3),y ; Get number of pages
+ sta ptr4+1
+
+ lda tmp1 ; extract bank/page
+ jsr setpage ; sets curbank/curpage
+ lda curpage
+ add #>BANK ; add to BANK address
+ sta STACK+16 ; current page in bank
+ ldx curbank
+ lda banks,x
+ sta STACK+10 ; set bank in stack
+ lda portb_save
+ sta STACK+2 ; set bank restore in stack
+ sta STACK+18 ; set final restore too
copyto_copy:
- lda ptr4 ; check if count is zero
- bne @4
- lda ptr4+1
- beq done
+ lda ptr4 ; check if count is zero
+ bne @4
+ lda ptr4+1
+ beq done
@4: jsr STACK ; copy one byte
- sec
- lda ptr4
- sub #1
- sta ptr4
- bcs @1
- lda ptr4+1
- beq @1
- sub #1
- sta ptr4+1
+ sec
+ lda ptr4
+ sub #1
+ sta ptr4
+ bcs @1
+ lda ptr4+1
+ beq @1
+ sub #1
+ sta ptr4+1
@1: inc STACK+15 ; increment address in BANK
- bne @2
- inc STACK+16
- lda STACK+16
- cmp #$80 ; we stepped outside bank
- bne @2
-
- inc curbank ; get next bank
- ldx curbank
- lda banks,x
- sta STACK+10 ; set new bank
- lda #$40 ; set address back to $4000
- sta STACK+16
+ bne @2
+ inc STACK+16
+ lda STACK+16
+ cmp #$80 ; we stepped outside bank
+ bne @2
+
+ inc curbank ; get next bank
+ ldx curbank
+ lda banks,x
+ sta STACK+10 ; set new bank
+ lda #$40 ; set address back to $4000
+ sta STACK+16
@2: inc STACK+7 ; increment buffer address
- bne @3
- inc STACK+8
+ bne @3
+ inc STACK+8
@3: jmp copyto_copy ; copy another byte
projects / cc65 / blobdiff