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ccp.asm
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ccp.asm
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; Reformatted and converted for cross-assembly by Macro Assembler AS
; Eric Smith <spacewar@gmail.com> 2018-01-24
; from original source os2ccp.asm from
; http://www.cpm.z80.de/download/cpm2-plm.zip
; Changes:
; multiple instructions per line split to separate lines
; dollar sign in labels replaced by underscore
; dollar sign (as digit separator) in binary constants removed
; single quotes around strings replaced with double quotes
; true and false replaced with _true and _false
; replaced "not" operator with "~"
; removed empty comments
; added ifdef origin to allow origin to be specified from command line
; added commments about serial number
; added ifdefs on "noserial" to omit serialization check
.cpu 8080
title "console command processor (CCP), ver 2.0"
; assembly language version of the CP/M console command processor
; version 2.2 February, 1980
; Copyright (c) 1976, 1977, 1978, 1979, 1980
; Digital Research
; Box 579, Pacific Grove,
; California, 93950
_false equ 0000h
_true equ ~_false
testing equ _false ;true if debugging
ifdef origin
org origin
bdosl equ $+800h ;bdos location
else
if testing
org 3400h
bdosl equ $+800h ;bdos location
else
org 000h
bdosl equ $+800h ;bdos location
endif
endif
tran equ 100h
tranm equ $
ccploc equ $
; ********************************************************
; * Base of CCP contains the following code/data *
; * ccp: jmp ccpstart (start with command) *
; * jmp ccpclear (start, clear command) *
; * ccp+6 127 (max command length) *
; * ccp+7 comlen (command length = 00) *
; * ccp+8 ' ... ' (16 blanks) *
; ********************************************************
; * Normal entry is at ccp, where the command line given *
; * at ccp+8 is executed automatically (normally a null *
; * command with comlen = 00). An initializing program *
; * can be automatically loaded by storing the command *
; * at ccp+8, with the command length at ccp+7. In this *
; * case, the ccp executes the command before prompting *
; * the console for input. Note that the command is exe-*
; * cuted on both warm and cold starts. When the command*
; * line is initialized, a jump to "jmp ccpclear" dis- *
; * ables the automatic command execution. *
; ********************************************************
jmp ccpstart ;start ccp with possible initial command
jmp ccpclear ;clear the command buffer
maxlen: db 127 ;max buffer length
comlen: db 0 ;command length (filled in by dos)
; (command executed initially if comlen non zero)
combuf:
db " " ;8 character fill
db " " ;8 character fill
db "COPYRIGHT (C) 1979, DIGITAL RESEARCH "; 38
ds 128-($-combuf)
; total buffer length is 128 characters
comaddr:dw combuf ;address of next to char to scan
staddr: ds 2 ;starting address of current fillfcb request
diska equ 0004h ;disk address for current disk
bdos equ 0005h ;primary bdos entry point
buff equ 0080h ;default buffer
fcb equ 005ch ;default file control block
rcharf equ 1 ;read character function
pcharf equ 2 ;print character function
pbuff equ 9 ;print buffer function
rbuff equ 10 ;read buffer function
breakf equ 11 ;break key function
liftf equ 12 ;lift head function (no operation)
initf equ 13 ;initialize bdos function
self equ 14 ;select disk function
openf equ 15 ;open file function
closef equ 16 ;close file function
searf equ 17 ;search for file function
searnf equ 18 ;search for next file function
delf equ 19 ;delete file function
dreadf equ 20 ;disk read function
dwritf equ 21 ;disk write function
makef equ 22 ;file make function
renf equ 23 ;rename file function
logf equ 24 ;return login vector
cself equ 25 ;return currently selected drive number
dmaf equ 26 ;set dma address
userf equ 32 ;set user number
; special fcb flags
rofile equ 9 ;read only file
sysfile equ 10 ;system file flag
; special characters
cr equ 13 ;carriage return
lf equ 10 ;line feed
la equ 5fh ;left arrow
eofile equ 1ah ;end of file
; utility procedures
printchar:
mov e,a
mvi c,pcharf
jmp bdos
printbc:
;print character, but save b,c registers
push b
call printchar
pop b
ret
crlf:
mvi a,cr
call printbc
mvi a,lf
jmp printbc
blank:
mvi a,' '
jmp printbc
print: ;print string starting at b,c until next 00 entry
push b ;now print the string
call crlf
pop h
prin0: mov a,m ;stop on 00
ora a
rz
inx h ;ready for next
push h
call printchar ;character printed
pop h
jmp prin0 ;for another character
initialize:
mvi c,initf
jmp bdos
select:
mov e,a
mvi c,self
jmp bdos
bdos_inr:
call bdos
sta dcnt
inr a
ret
open: ;open the file given by d,e
mvi c,openf
jmp bdos_inr
openc: ;open comfcb
xra a ;clear next record to read
sta comrec
lxi d,comfcb
jmp open
close: ;close the file given by d,e
mvi c,closef
jmp bdos_inr
search: ;search for the file given by d,e
mvi c,searf
jmp bdos_inr
searchn:
;search for the next occurrence of the file given by d,e
mvi c,searnf
jmp bdos_inr
searchcom:
;search for comfcb file
lxi d,comfcb
jmp search
delete: ;delete the file given by d,e
mvi c,delf
jmp bdos
bdos_cond:
call bdos
ora a
ret
diskread:
;read the next record from the file given by d,e
mvi c,dreadf
jmp bdos_cond
diskreadc:
;read the comfcb file
lxi d,comfcb
jmp diskread
diskwrite:
;write the next record to the file given by d,e
mvi c,dwritf
jmp bdos_cond
make: ;create the file given by d,e
mvi c,makef
jmp bdos_inr
renam: ;rename the file given by d,e
mvi c,renf
jmp bdos
getuser:
;return current user code in a
mvi e,0ffh ;drop through to setuser
setuser:
mvi c,userf ;sets user number
jmp bdos
saveuser:
;save user#/disk# before possible ^c or transient
call getuser ;code to a
add a ;rot left
add a
add a
add a
lxi h,cdisk ;4b=user, 4b=disk
ora m
sta diska ;stored away in memory for later
ret
setdiska:
lda cdisk ;user/disk
sta diska
ret
translate:
;translate character in register A to upper case
cpi 61h ;return if below lower case a
rc
cpi 7bh ;return if above lower case z
rnc
ani 5fh ;translated to upper case
ret
readcom:
;read the next command into the command buffer
;check for submit file
lda submit
ora a
jz nosub
;scanning a submit file
;change drives to open and read the file
lda cdisk
ora a
mvi a,0
cnz select
;have to open again in case xsub present
lxi d,subfcb ;skip if no sub
call open
jz nosub
lda subrc ;read last record(s) first
dcr a
sta subcr ;current record to read
lxi d,subfcb ;end of file if last record
call diskread
jnz nosub
;disk read is ok, transfer to combuf
lxi d,comlen
lxi h,buff
mvi b,128
call move0
;line is transferred, close the file with a
;deleted record
lxi h,submod ;clear fwflag
mvi m,0
inx h ;one less record
dcr m
lxi d,subfcb
call close
jz nosub
;close went ok, return to original drive
lda cdisk
ora a
cnz select
;print to the 00
lxi h,combuf
call prin0
call break_key
jz noread
call del_sub ;break key depressed
jmp ccp
nosub: ;no submit file
call del_sub
;translate to upper case, store zero at end
call saveuser ;user # save in case control c
mvi c,rbuff
lxi d,maxlen
call bdos
call setdiska ;no control c, so restore diska
noread: ;enter here from submit file
;set the last character to zero for later scans
lxi h,comlen ;length is in b
mov b,m
readcom0:
inx h ;end of scan?
mov a,b
ora a
jz readcom1 ;get character and translate
mov a,m
call translate
mov m,a
dcr b
jmp readcom0
readcom1: ;end of scan, h,l address end of command
mov m,a ;store a zero
lxi h,combuf ;ready to scan to zero
shld comaddr
ret
break_key:
;check for a character ready at the console
mvi c,breakf
call bdos
ora a
rz
mvi c,rcharf ;character cleared
call bdos
ora a
ret
cselect:
;get the currently selected drive number to reg-A
mvi c,cself
jmp bdos
setdmabuff:
;set default buffer dma address
lxi d,buff ;(drop through)
setdma:
;set dma address to d,e
mvi c,dmaf
jmp bdos
del_sub:
;delete the submit file, and set submit flag to false
lxi h,submit ;return if no sub file
mov a,m
ora a
rz
mvi m,0 ;submit flag is set to false
xra a ;on drive a to erase file
call select
lxi d,subfcb
call delete
lda cdisk ;back to original drive
jmp select
ifndef noserial
serialize:
;check serialization
lxi d,serial ;check six bytes
lxi h,bdosl
mvi b,6
ser0: ldax d
cmp m
jnz badserial
inx d
inx h
dcr b
jnz ser0
ret ;serial number is ok
endif
comerr:
;error in command string starting at position
;'staddr' and ending with first delimiter
call crlf ;space to next line
lhld staddr ;h,l address first to print
comerr0: ;print characters until blank or zero
mov a,m ; not blank
cpi ' '
jz comerr1
ora a ; not zero, so print it
jz comerr1
push h
call printchar
pop h
inx h
jmp comerr0; for another character
comerr1: ;print question mark,and delete sub file
mvi a,'?'
call printchar
call crlf
call del_sub
jmp ccp ;restart with next command
; fcb scan and fill subroutine (entry is at fillfcb below)
;fill the comfcb, indexed by A (0 or 16)
;subroutines
delim: ;look for a delimiter
ldax d ;not the last element
ora a
rz
cpi ' ' ;non graphic
jc comerr
rz ;treat blank as delimiter
cpi '='
rz
cpi la ;left arrow
rz
cpi '.'
rz
cpi ':'
rz
cpi ';'
rz
cpi '<'
rz
cpi '>'
rz
ret ;delimiter not found
deblank: ;deblank the input line
ldax d ;treat end of line as blank
ora a
rz
cpi ' '
rnz
inx d
jmp deblank
addh: ;add a to h,l
add l
mov l,a
rnc
inr h
ret
fillfcb0:
;equivalent to fillfcb(0)
mvi a,0
fillfcb:
lxi h,comfcb ;fcb rescanned at end
call addh
push h
push h
xra a ;clear selected disk (in case A:...)
sta sdisk
lhld comaddr ;command address in d,e
xchg
call deblank ;to first non-blank character
xchg ;in case of errors
shld staddr
xchg ;d,e has command, h,l has fcb address
pop h
;look for preceding file name A: B: ...
ldax d ;use current disk if empty command
ora a
jz setcur0
sbi 'A'-1 ;disk name held in b if : follows
mov b,a
inx d ;set disk name if :
ldax d
cpi ':'
jz setdsk
setcur: ;set current disk
dcx d ;back to first character of command
setcur0:
lda cdisk
mov m,a
jmp setname
setdsk: ;set disk to name in register b
mov a,b ;mark as disk selected
sta sdisk
mov m,b ;past the :
inx d
setname: ;set the file name field
mvi b,8 ;file name length (max)
setnam0:
call delim ;not a delimiter
jz padname
inx h ;must be ?'s
cpi '*'
jnz setnam1
mvi m,'?' ;to dec count
jmp setnam2
setnam1:
mov m,a ;store character to fcb
inx d
setnam2:
dcr b ;count down length
jnz setnam0
;end of name, truncate remainder
trname: call delim ;set type field if delimiter
jz setty
inx d
jmp trname
padname:
inx h
mvi m,' '
dcr b
jnz padname
setty: ;set the type field
mvi b,3 ;skip the type field if no .
cpi '.'
jnz padty
inx d ;past the ., to the file type field
setty0: ;set the field from the command buffer
call delim
jz padty
inx h
cpi '*'
jnz setty1
mvi m,'?' ;since * specified
jmp setty2
setty1: ;not a *, so copy to type field
mov m,a
inx d
setty2: ;decrement count and go again
dcr b
jnz setty0
;end of type field, truncate
trtyp: ;truncate type field
call delim
jz efill
inx d
jmp trtyp
padty: ;pad the type field with blanks
inx h
mvi m,' '
dcr b
jnz padty
efill: ;end of the filename/filetype fill, save command address
;fill the remaining fields for the fcb
mvi b,3
efill0: inx h
mvi m,0
dcr b
jnz efill0
xchg ;set new starting point
shld comaddr
;recover the start address of the fcb and count ?'s
pop h ;b=0, c=8+3
lxi b,11
scnq: inx h
mov a,m
cpi '?'
jnz scnq0
;? found, count it in b
inr b
scnq0: dcr c
jnz scnq
;number of ?'s in c, move to a and return with flags set
mov a,b
ora a
ret
intvec:
;intrinsic function names (all are four characters)
db "DIR "
db "ERA "
db "TYPE"
db "SAVE"
db "REN "
db "USER"
intlen equ ($-intvec)/4 ;intrinsic function length
; serial number (details not documented in original DRI source file)
serial: db 0 ; OEM number, low byte
db 0 ; CP/M version, 16h = 2.2
db 0 ; OEM number, high byte
db 0,0,0 ; serial number, big-endian
intrinsic:
;look for intrinsic functions (comfcb has been filled)
lxi h,intvec ;c counts intrinsics as scanned
mvi c,0
intrin0:
mov a,c ;done with scan?
cpi intlen
rnc
;no, more to scan
lxi d,comfcb+1 ;beginning of name
mvi b,4 ;length of match is in b
intrin1:
ldax d ;match?
cmp m
jnz intrin2 ;skip if no match
inx d
inx h
dcr b
jnz intrin1 ;loop while matching
;complete match on name, check for blank in fcb
ldax d ;otherwise matched
cpi ' '
jnz intrin3
mov a,c ;with intrinsic number in a
ret
intrin2: ;mismatch, move to end of intrinsic
inx h
dcr b
jnz intrin2
intrin3: ;try next intrinsic
inr c ;to next intrinsic number
jmp intrin0 ;for another round
ccpclear:
;clear the command buffer
xra a
sta comlen
;drop through to start ccp
ccpstart:
;enter here from boot loader
lxi sp,stack ;save initial disk number
push b
;(high order 4bits=user code, low 4bits=disk#)
mov a,c ;user code
rar
rar
rar
rar
ani 0fh
mov e,a ;user code selected
call setuser
;initialize for this user, get $ flag
call initialize ;0ffh in accum if $ file present
sta submit ;submit flag set if $ file present
pop b ;recall user code and disk number
mov a,c ;disk number in accumulator
ani 0fh
sta cdisk ;clears user code nibble
call select ;proper disk is selected, now check sub files
;check for initial command
lda comlen ;assume typed already
ora a
jnz ccp0
ccp:
;enter here on each command or error condition
lxi sp,stack
call crlf ;print d> prompt, where d is disk name
call cselect ;get current disk number
adi 'A'
call printchar
mvi a,'>'
call printchar
call readcom ;command buffer filled
ccp0: ;(enter here from initialization with command full)
lxi d,buff ;default dma address at buff
call setdma
call cselect ;current disk number saved
sta cdisk
call fillfcb0 ;command fcb filled
cnz comerr ;the name cannot be an ambiguous reference
lda sdisk
ora a
jnz userfunc
;check for an intrinsic function
call intrinsic
lxi h,jmptab ;index is in the accumulator
mov e,a ;index in d,e
mvi d,0
dad d
dad d
mov a,m
inx h
mov h,m
mov l,a
pchl
;pc changes to the proper intrinsic or user function
jmptab:
dw direct ;directory search
dw erase ;file erase
dw type ;type file
dw save ;save memory image
dw rename ;file rename
dw user ;user number
dw userfunc;user-defined function
ifndef noserial
badserial:
LXI H,76F3H ;'DI HLT' instructions.
;typo "lxi h,di or (hlt shl 8)" here originally,
;corrected by comparing to disassembly of Clark Calkins.
shld ccploc
lxi h,ccploc
pchl
endif
;utility subroutines for intrinsic handlers
readerr:
;print the read error message
lxi b,rdmsg
jmp print
rdmsg: db "READ ERROR",0
nofile:
;print no file message
lxi b,nofmsg
jmp print
nofmsg: db "NO FILE",0
getnumber: ;read a number from the command line
call fillfcb0 ;should be number
lda sdisk ;cannot be prefixed
ora a
jnz comerr
;convert the byte value in comfcb to binary
lxi h,comfcb+1 ;(b=0, c=11)
lxi b,11
;value accumulated in b, c counts name length to zero
conv0: mov a,m
cpi ' '
jz conv1
;more to scan, convert char to binary and add
inx h ;valid?
sui '0'
cpi 10
jnc comerr
mov d,a ;save value
mov a,b ;mult by 10
ani 11100000b
jnz comerr
mov a,b ;recover value
rlc ;*8
rlc
rlc
add b
jc comerr
add b ;*8+*2 = *10
jc comerr
add d ;+digit
jc comerr
mov b,a ;for another digit
dcr c
jnz conv0
ret
conv1: ;end of digits, check for all blanks
mov a,m ;blanks?
cpi ' '
jnz comerr
inx h
dcr c
jnz conv1
mov a,b ;recover value
ret
movename:
;move 3 characters from h,l to d,e addresses
mvi b,3
move0: mov a,m
stax d
inx h
inx d
dcr b
jnz move0
ret
addhcf: ;buff + a + c to h,l followed by fetch
lxi h,buff
add c
call addh
mov a,m
ret
setdisk:
;change disks for this command, if requested
xra a ;clear disk name from fcb
sta comfcb
lda sdisk ;no action if not specified
ora a
rz
dcr a ;already selected
lxi h,cdisk
cmp m
rz
jmp select
resetdisk:
;return to original disk after command
lda sdisk ;no action if not selected
ora a
rz
dcr a ;same disk
lxi h,cdisk
cmp m
rz
lda cdisk
jmp select
;individual intrinsics follow
direct:
;directory search
call fillfcb0 ;comfcb gets file name
call setdisk ;change disk drives if requested
lxi h,comfcb+1 ;may be empty request
mov a,m
cpi ' ' ;skip fill of ??? if not blank
jnz dir1
;set comfcb to all ??? for current disk
mvi b,11 ;length of fill ????????.???
dir0: mvi m,'?'
inx h
dcr b
jnz dir0
;not a blank request, must be in comfcb
dir1: mvi e,0 ;E counts directory entries
push d
call searchcom ;first one has been found
cz nofile ;not found message
dir2: jz endir
;found, but may be system file
lda dcnt ;get the location of the element
rrc
rrc
rrc
ani 1100000b
mov c,a
;c contains base index into buff for dir entry
mvi a,sysfile ;value to A
call addhcf
ral ;skip if system file
jc dir6
;c holds index into buffer
;another fcb found, new line?
pop d
mov a,e
inr e
push d
;e=0,1,2,3,...new line if mod 4 = 0
ani 11b ;and save the test
push psw
jnz dirhdr0 ;header on current line
call crlf
push b
call cselect
pop b
;current disk in A
adi 'A'
call printbc
mvi a,':'
call printbc
jmp dirhdr1 ;skip current line hdr
dirhdr0:
call blank ;after last one
mvi a,':'
call printbc
dirhdr1:
call blank
;compute position of name in buffer
mvi b,1 ;start with first character of name
dir3: mov a,b ;buff+a+c fetched
call addhcf
ani 7fh ;mask flags
;may delete trailing blanks
cpi ' ' ;check for blank type
jnz dir4
pop psw ;may be 3rd item
push psw
cpi 3 ;place blank at end if not
jnz dirb
mvi a,9 ;first char of type
call addhcf
ani 7fh
cpi ' '
jz dir5
;not a blank in the file type field
dirb: mvi a,' ' ;restore trailing filename chr
dir4:
call printbc ;char printed
inr b
mov a,b
cpi 12
jnc dir5
;check for break between names
cpi 9 ;for another char
jnz dir3
;print a blank between names
call blank
jmp dir3
dir5: ;end of current entry
pop psw ;discard the directory counter (mod 4)
dir6: call break_key ;check for interrupt at keyboard
jnz endir ;abort directory search
call searchn ;for another entry
jmp dir2
endir: ;end of directory scan
pop d ;discard directory counter
jmp retcom
erase:
call fillfcb0 ;cannot be all ???'s
cpi 11
jnz erasefile
;erasing all of the disk
lxi b,ermsg
call print
call readcom
lxi h,comlen ;bad input
dcr m
jnz ccp
inx h
mov a,m
cpi 'Y'
jnz ccp
;ok, erase the entire diskette
inx h ;otherwise error at retcom
shld comaddr
erasefile:
call setdisk
lxi d,comfcb
call delete
inr a ;255 returned if not found
cz nofile ;no file message if so
jmp retcom
ermsg: db "ALL (Y/N)?",0
type:
call fillfcb0 ;don't allow ?'s in file name
jnz comerr
call setdisk ;open the file
call openc
jz typerr ;zero flag indicates not found
;file opened, read 'til eof
call crlf ;read first buffer
lxi h,bptr
mvi m,255
type0: ;loop on bptr
lxi h,bptr ;end buffer
mov a,m
cpi 128
jc type1 ;carry if 0,1,...,127
push h
;read another buffer full
call diskreadc
pop h ;recover address of bptr
jnz typeof ;hard end of file
xra a ;bptr = 0
mov m,a
type1: ;read character at bptr and print
inr m ;bptr = bptr + 1
lxi h,buff ;h,l addresses char
call addh
mov a,m
cpi eofile
jz retcom
call printchar
call break_key ;abort if break
jnz retcom
jmp type0 ;for another character