extrn @dtbl ; table of pointers to XDPHs\r
public @adrv,@rdrv,@trk,@sect ; parameters for disk I/O\r
public @dma,@dbnk,@cnt ; '' '' '' ''\r
+ public @xdph,@op\r
\r
; memory control\r
\r
\r
; External names for BIOS entry points\r
\r
- public ?boot,?wboot,?const,?conin,?cono,?list,?auxo,?auxi\r
+ public ?boot,?wboot,boot,?const,?conin,?cono,?list,?auxo,?auxi\r
public ?home,?sldsk,?sttrk,?stsec,?stdma,?read,?write\r
public ?lists,?sctrn\r
public ?conos,?auxis,?auxos,?dvtbl,?devin,?drtbl\r
dseg ; this part can be banked\r
\r
boot:\r
+ ld a,SYS$CBR\r
+ out0 (cbr),a\r
+ ld a,USR$CBAR\r
+ out0 (cbar),a\r
ld sp,bs$stack\r
\r
call hwinit ; first time hardware initialisation\r
add hl,hl ; shift out next bit\r
jr nc,not$out$device\r
push hl ; save the vector\r
-; push bc ; save the count and character\r
-;not$out$ready:\r
-; call coster\r
-; or a\r
-; jr z,not$out$ready\r
-; pop bc\r
- push bc ; restore and resave the character and device\r
+ push bc ; save device num and the character\r
call ?co ; if device selected, print it\r
pop bc ; recover count and character\r
pop hl ; recover the rest of the vector\r
push hl ; save the vector\r
push bc ; save the count\r
ld a,0FFh ; assume device ready\r
- call c,coster ; check status for this device\r
+ call c,?cost ; check status for this device\r
pop bc ; recover count\r
pop hl ; recover bit vector\r
or a ; see if device ready\r
or 0FFh ; all selected were ready, return true\r
ret\r
\r
- ; check for output device ready, including optional\r
- ; xon/xoff support\r
-coster:\r
- ld l,b\r
- ld h,0 ; make device code 16 bits\r
- push hl ; save it in stack\r
- add hl,hl\r
- add hl,hl\r
- add hl,hl ; create offset into device characteristics tbl\r
- ld de,@ctbl+6\r
- add hl,de ; make address of mode byte\r
- ld a,(hl)\r
- and mb$xon$xoff\r
- pop hl ; recover console number in <HL>\r
- jp z,?cost ; not a xon device, go get output status direct\r
- ld de,xofflist\r
- add hl,de ; make pointer to proper xon/xoff flag\r
- call cist1 ; see if this keyboard has character\r
- ld a,(hl)\r
- call nz,ci1 ; get flag or read key if any\r
- cp ctlq\r
- jr nz,not$q ; if its a ctl-Q,\r
- ld a,0FFh ; set the flag ready\r
-not$q:\r
- cp ctls\r
- jr nz,not$s ; if its a ctl-S,\r
- ld a,00h ; clear the flag\r
-not$s:\r
- ld (hl),a ; save the flag\r
- call cost1 ; get the actual output status,\r
- and (hl) ; and mask with ctl-Q/ctl-S flag\r
- ret ; return this as the status\r
\r
cist1: ; get input status with <BC> and <HL> saved\r
push bc\r
or a\r
ret\r
\r
-cost1: ; get output status, saving <BC> & <HL>\r
- push bc\r
- push hl\r
- call ?cost\r
- pop hl\r
- pop bc\r
- or a\r
- ret\r
-\r
-ci1: ; get input, saving <BC> & <HL>\r
- push bc\r
- push hl\r
- call ?ci\r
- pop hl\r
- pop bc\r
- ret\r
-\r
\r
; AUXIST\r
; Auxiliary Input Status. Return true if\r
ist$scan:\r
ld b,0 ; start with device 0\r
cis$next:\r
- add hl,hl ; check next bit\r
- ld a,0 ; assume device not ready\r
- call c,cist1 ; check status for this device\r
- or a\r
+ xor a ; assume next device not ready\r
+ add hl,hl ; check next bit (lets z flag unaffected)\r
+ call c,cist1 ; check status for this device\r
ret nz ; if any ready, return true\r
inc b ; next device number\r
ld a,h\r
or l ; see if any more selected devices\r
- jr nz,cis$next\r
- xor a ; all selected were not ready, return false\r
- ret\r
+ ret z ; all selected were not ready, return false\r
+ jr cis$next\r
\r
\r
; AUXIN\r
push hl ; save bit vector\r
ld b,0\r
ci$next:\r
+ xor a ; assume next device not ready\r
add hl,hl ; shift out next bit\r
- ld a,0 ; insure zero a (nonexistant device not ready).\r
call c,cist1 ; see if the device has a character\r
- or a\r
jr nz,ci$rdy ; this device has a character\r
inc b ; else, next device\r
ld a,h\r
jp ?bank ; and go exit through users\r
; physical bank select routine\r
\r
-\r
-xofflist:\r
- db -1,-1,-1,-1,-1,-1,-1,-1 ; ctl-s clears to zero\r
- db -1,-1,-1,-1,-1,-1,-1,-1\r
-\r
dseg ; following resides in banked memory\r
\r
; Disk I/O interface routines\r
seldsk:\r
ld a,c ; save drive select code\r
ld (@adrv),a\r
- ld b,0 ; create index from drive code\r
+ xor a\r
+ ld (@op),a\r
+ ld (@cnt),a\r
+ ld b,a ; create index from drive code\r
ld hl,@dtbl\r
add hl,bc ; get pointer to dispatch table\r
add hl,bc\r
or h\r
ret z ; if no entry in table, no disk\r
\r
- ld a,e ; examine login bit\r
- and 1\r
- ret nz\r
-\r
- push ix\r
- ld ix,(@xdph)\r
- ld a,(ix-2)\r
- ld (@RDRV),a ; get relative drive\r
- ld l,(ix-6) ; get address of LOGIN routine\r
- ld h,(ix-5)\r
- ex (sp),ix\r
- pop de\r
+ bit 0,e ; login bit to zero flag\r
+ ex de,hl\r
+ ld hl,-2 ; get relative drive\r
+ add hl,de\r
+ ld a,(hl)\r
+ ld (@RDRV),a\r
+ jr nz,notfirst ; examine login bit\r
+ ld hl,-6\r
+ add hl,de\r
+ ld a,(hl)\r
+ inc hl\r
+ ld h,(hl)\r
+ ld l,a\r
call ipchl ; call LOGIN\r
+notfirst:\r
ld hl,(@xdph) ; recover DPH pointer\r
ret\r
\r
; extended disk parameter header (XDPH).\r
\r
read:\r
+ ld a,1\r
+ ld (@op),a\r
ld ix,(@xdph) ; get drive descriptor pointer\r
ld l,(ix-8) ; get read routine entry\r
ld h,(ix-7)\r
; extended disk parameter header (XDPH).\r
\r
write:\r
+ ld a,2\r
+ ld (@op),a\r
ld ix,(@xdph) ; get drive descriptor pointer\r
ld l,(ix-10) ; get write routine entry\r
ld h,(ix- 9)\r
; do not change order. sd driver depends on this\r
\r
@xdph: ds 2 ; pointer to currently selected drives dph\r
+@op ds 1 ; current disk operation 0:select, 1:read, 2 write\r
@adrv: ds 1 ; currently selected disk drive\r
@rdrv: ds 1 ; controller relative disk drive\r
@trk: ds 2 ; current track number\r
projects / z180-stamp-cpm3.git / blobdiff