From: uz Date: Tue, 2 Feb 2010 18:32:34 +0000 (+0000) Subject: New EMD driver for the ISEPIC cartridge written and contributed by X-Git-Tag: V2.13.2~27 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=4e18dad55a21955e811ecca92aa4e39323f64a6b;p=cc65 New EMD driver for the ISEPIC cartridge written and contributed by Marco van den Heuvel with some cleanup by me. git-svn-id: svn://svn.cc65.org/cc65/trunk@4574 b7a2c559-68d2-44c3-8de9-860c34a00d81 --- diff --git a/libsrc/c64/Makefile b/libsrc/c64/Makefile index eb0d41226..747516a8a 100644 --- a/libsrc/c64/Makefile +++ b/libsrc/c64/Makefile @@ -71,15 +71,26 @@ OBJS = _scrsize.o \ #-------------------------------------------------------------------------- # Drivers -EMDS = c64-georam.emd c64-ram.emd c64-ramcart.emd c64-reu.emd c64-vdc.emd dtv-himem.emd - -JOYS = c64-hitjoy.joy c64-numpad.joy c64-ptvjoy.joy c64-stdjoy.joy - -MOUS = c64-1351.mou c64-joymouse.mou c64-potmouse.mou - -SERS = c64-swlink.ser - -TGIS = c64-320-200-2.tgi +EMDS = c64-georam.emd \ + c64-isepic.emd \ + c64-ram.emd \ + c64-ramcart.emd \ + c64-reu.emd \ + c64-vdc.emd \ + dtv-himem.emd + +JOYS = c64-hitjoy.joy \ + c64-numpad.joy \ + c64-ptvjoy.joy \ + c64-stdjoy.joy + +MOUS = c64-1351.mou \ + c64-joymouse.mou \ + c64-potmouse.mou + +SERS = c64-swlink.ser + +TGIS = c64-320-200-2.tgi #-------------------------------------------------------------------------- # Targets diff --git a/libsrc/c64/c64-isepic.s b/libsrc/c64/c64-isepic.s new file mode 100755 index 000000000..533dfaffa --- /dev/null +++ b/libsrc/c64/c64-isepic.s @@ -0,0 +1,270 @@ +; +; Extended memory driver for the ISEPIC cartridge. +; Marco van den Heuvel, 2010-01-24 +; + + .include "zeropage.inc" + + .include "em-kernel.inc" + .include "em-error.inc" + + + .macpack generic + + +; ------------------------------------------------------------------------ +; Header. Includes jump table + +.segment "JUMPTABLE" + +; Driver signature + + .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 + +; ------------------------------------------------------------------------ +; Constants + +IP_WINDOW = $DF00 ; Address of ISEPIC window +IP_CTRL_BASE = $DE00 +PAGES = 8 + +; ------------------------------------------------------------------------ +; Code. + +.code + +; ------------------------------------------------------------------------ +; INSTALL routine. Is called after the driver is loaded into memory. If +; possible, check if the hardware is present and determine the amount of +; memory available. +; Must return an EM_ERR_xx code in a/x. +; + +INSTALL: + lda #0 + sta IP_CTRL_BASE + ldx IP_WINDOW + cpx IP_WINDOW + bne @notpresent + inc IP_WINDOW + cpx IP_WINDOW + beq @notpresent + ldx IP_WINDOW + sta IP_CTRL_BASE+1 + inx + stx IP_WINDOW + dex + sta IP_CTRL_BASE + cpx IP_WINDOW + beq @setok + +@notpresent: + lda #EM_ERR_NO_DEVICE + rts + +@setok: + lda #EM_ERR_OK +; rts ; Run into UNINSTALL instead + +; ------------------------------------------------------------------------ +; UNINSTALL routine. Is called before the driver is removed from memory. +; Can do cleanup or whatever. Must not return anything. +; + +UNINSTALL: + rts + +; ------------------------------------------------------------------------ +; PAGECOUNT: Return the total number of available pages in a/x. +; + +PAGECOUNT: + lda #PAGES + rts + +; ------------------------------------------------------------------------ +; USE: Tell the driver that the window is now associated with a given page. +; The Isepic cartridge does not copy but actually map the window, so USE is +; identical to MAP. + +USE := MAP + +; ------------------------------------------------------------------------ +; MAP: Map the page in a/x into memory and return a pointer to the page in +; a/x. The contents of the currently mapped page (if any) may be discarded +; by the driver. +; + +MAP: + tax + sta IP_CTRL_BASE,x + lda #IP_WINDOW + +; Use the RTS from COMMIT below to save a precious byte of storage + +; ------------------------------------------------------------------------ +; COMMIT: Commit changes in the memory window to extended storage. + +COMMIT: + rts + +; ------------------------------------------------------------------------ +; COPYFROM: Copy from extended into linear memory. A pointer to a structure +; describing the request is passed in a/x. +; The function must not return anything. +; + +COPYFROM: + jsr setup + +; Setup is: +; +; - ptr1 contains the struct pointer +; - ptr2 contains the linear memory buffer +; - ptr3 contains -(count-1) +; - tmp1 contains the low page register value +; - X contains the page offset +; - Y contains zero + + jmp @L5 + +@L1: + lda IP_WINDOW,x + sta (ptr2),y + iny + bne @L2 + inc ptr2+1 +@L2: + inx + beq @L4 + +; Bump count and repeat + +@L3: + inc ptr3 + bne @L1 + inc ptr3+1 + bne @L1 + rts + +; Bump page register + +@L4: + inc tmp1 ; Bump low page register +@L5: + stx tmp2 + ldx tmp1 + sta IP_CTRL_BASE,x + ldx tmp2 + jmp @L3 + +; ------------------------------------------------------------------------ +; COPYTO: Copy from linear into extended memory. A pointer to a structure +; describing the request is passed in a/x. +; The function must not return anything. +; + +COPYTO: + jsr setup + +; Setup is: +; +; - ptr1 contains the struct pointer +; - ptr2 contains the linear memory buffer +; - ptr3 contains -(count-1) +; - tmp1 contains the low page register value +; - X contains the page offset +; - Y contains zero + + jmp @L5 + +@L1: + lda (ptr2),y + sta IP_WINDOW,x + iny + bne @L2 + inc ptr2+1 +@L2: + inx + beq @L4 + +; Bump count and repeat + +@L3: + inc ptr3 + bne @L1 + inc ptr3+1 + bne @L1 + rts + +; Bump page register + +@L4: + inc tmp1 ; Bump page register +@L5: + stx tmp2 + ldx tmp1 + sta IP_CTRL_BASE,x + ldx tmp2 + 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 + +; Get the page number from the struct and remember it. + + ldy #EM_COPY::PAGE + lda (ptr1),y + sta tmp1 + +; Get the buffer pointer into ptr2 + + ldy #EM_COPY::BUF + lda (ptr1),y + sta ptr2 + iny + 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 + iny + lda (ptr1),y + eor #$FF + sta ptr3+1 + +; Get the page offset into X and clear Y + + ldy #EM_COPY::OFFS + lda (ptr1),y + tax + ldy #0 + +; Done + + rts