A: to P: drives supported

Author: nihirash

bin/cpm.bin

@@ -27,7 +27,7 @@ _main:
 	ld a, CPM_SEG
 	ld mb, a
 	stmix
-	jp.sis $E1FD
+	jp.sis $DCFD
 
 _error:
 	xor a
@@ -47,7 +47,7 @@ _error:
 
 _cpm_restore:
 	ld hl, _cpm_image
-	ld de, $5E1FD
+	ld de, $5dcfd
 	ld bc, _cpm_end - _cpm_image
 	ldir
 	ret.lil

bootstrap/cpm.asm

@@ -74,64 +74,56 @@ _drive_write:
 	ret.lil
 	
 
-drive_a:
-	db "cpma.dsk", 0
-drive_b:
-	db "cpmb.dsk", 0
-drive_c:
-	db "cpmc.dsk", 0
-drive_d:
-	db "cpmd.dsk", 0
+drive:
+	db "cpm"
+drive_letter:
+	db "a.dsk", 0
 
 
 f_handle: db 0
 
-f_a:	db 0
-f_b:	db 0
-f_c:	db 0
-f_d:	db 0
-
 _drive_change:
-	ld de, f_a
-	or a
-	sbc hl, hl
-	ld l, a
-	add hl, de
-	ld a, (hl)
-	ld (f_handle), a
-	ret.lil
-	
+	add a, 'a'
+	ld (drive_letter), a
+	xor a
+	ld mb, a
 
-fs_init:
-	ld c, 0
+	ld a, (f_handle)
 	MOSCALL mos_fclose
 
-	ld hl, drive_a
+	ld hl, drive
 	ld c, fa_read+fa_write
 	MOSCALL mos_fopen
-	ld (f_a), a
+
+	ld (f_handle), a
 	or a
-	ret z
+	jr z, _dr_change_err
 
-	ld hl, drive_b
-	ld c, fa_read+fa_write
-	MOSCALL mos_fopen
-	ld (f_b), a
-	
-	ld hl, drive_c
-	ld c, fa_read+fa_write
-	MOSCALL mos_fopen
-	ld (f_c), a
-	
-	ld hl, drive_d
+	push af
+	ld a, CPM_SEG
+	ld mb, a
+	pop af
+	ret.lil
+
+_dr_change_err:
+	xor a
+	call.lil _drive_change
+
+	ld a, CPM_SEG
+	ld mb, a
+	xor a
+	ret.lil	
+
+fs_init:
+	ld c, 0
+	MOSCALL mos_fclose
+
+	ld hl, drive
 	ld c, fa_read+fa_write
 	MOSCALL mos_fopen
-	ld (f_d), a
-
-	ld a, (f_a)
 	ld (f_handle), a
 	or a
-	ret
+	ret 
 
 fs_seek:
 	add hl, hl ; *2

bootstrap/drive_emu.inc

@@ -39,6 +39,71 @@ dbp_size = $ - dbp
     dw	dirbf, dpblk
     dw	$0000, all03
 
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all04
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all05
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all06
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all07
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all08
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all09
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all10
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all10
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all11
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all12
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all13
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all14
+
+    dw  $0000, $0000
+    dw  $0000, $0000
+    dw	dirbf, dpblk
+    dw	$0000, all15
+
 dpblk:	;disk parameter block for all disks.
     dw	64	;sectors per track
     db	6		;block shift factor
@@ -64,7 +129,7 @@ nothing:
     ret
 
 seldisk:
-    cp 4
+    cp 16
     jr nc, .ouch
 
     ld (.drive_num), a ;; It's more safe than joungling with stack(ONLY HERE!)
@@ -119,6 +184,18 @@ all00:  ds 128
 all01:  ds 128 
 all02:  ds 128 
 all03:  ds 128 
+all04:  ds 128 
+all05:  ds 128 
+all06:  ds 128 
+all07:  ds 128 
+all08:  ds 128
+all09:  ds 128 
+all10:  ds 128 
+all11:  ds 128 
+all12:  ds 128
+all13:  ds 128 
+all14:  ds 128 
+all15:  ds 128
 
 dirbf:  ds 128
 

sources/bios/bios.asm

@@ -1,6 +1,6 @@
     device zxspectrum48
     
-    org $e200-3
+    org $dd00-3
     DISPLAY "ORG: ", $
 cpm:
     jp BOOT