Date: Thursday, 22 August 1985
From: Bruce Conroy <blc at JPL-VLSI.ARPA>
To: info-cpm at AMSAA.ARPA
Re: dBaseII machine language interface
Here is a sample dBaseII file which loads and calls a machine
language program.
* dBase II file to read diskcat files into dBase format
* 85.0212 BLC
*--!---!---!---!
* modified to load and use diread.z80
* 85.0403 BLC
* uses variable for catalog name, to allow several catalogs
* 85.0405 BLC
set delete on
set talk off
accept 'Date' to today
set date to &today
load diread
accept 'Catalog to Use' to diskcat
use &diskcat
do while T
text
options are:
<D>isk ID order
<E>xtention order
<F>ull Printout
<N>ame order
<Q>ualified Printout
<S>earch for File
<U>pdate catalog
endtext
wait to command
store !(command) to command
if command='D'
index on disk:id+name+ext to disk
endif
if command='E'
index on ext+name+disk:id to ext
endif
if command='F'
store 'T' to qual
do printout
endif
if command='N'
index on name+ext+disk:id to name
endif
if command='Q'
accept 'Selection Function? ' to qual
store !(qual) to qual
do printout
endif
if command='S'
accept 'Search for? ' to qual
find &qual
disp
endif
if command='U'
* directory read
* 85.0403 BLC
? 'Put new disk in B and press <return>'
wait
reset
copy stru to dir
use dir
store 'UNKNOWN' to d:id
store 'xxxxxxxxxxx' to entry
set call to 41984
call entry
set call to 41987
do while entry # 'NO DATA'
if $(entry,9,3)="DID"
store $(entry,1,8) to d:id
else
append blank
replace name with $(entry,1,8)
replace ext with $(entry,9,3)
replace cat:date with date()
endif
call entry
enddo
if d:id = 'UNKNOWN'
? 'No ID present'
use &diskcat
else
replace all disk:id with d:id
use &diskcat
delete all for disk:id=d:id
append from dir
endif
enddo
The machine language program is created by:
; diread.z80
; directory reading program to call from dBase
; 85.0403 BLC
;---!---!---!---!
; buffer added
; 85.0403 BLC
public one, two
cseg
.z80
bdos equ 5
findf equ 17 ;find first funct
findn equ 18 ; " next "
dmaf equ 26
one: jp first ;a400h=41984
two: jp next :a403h=41987
fcb: db 2 ; code for drive B
db "???????????" ;for name and ext
ds 24,0 ;rest of fcb all zeroed
psave: dw 0 ;save the passed parameter
empty: db "NO DATA "
buffer: ds 128 ;reserve a buffer
first: ld c,findf
jp endup
next: ld c,findn
endup: inc hl ;skip the length byte of dBase string
ld (psave),hl ;save the address
push bc ;save the function
ld de,buffer ;set dma to buffer
ld c,dmaf
call bdos
pop bc ; first or next back
ld de,fcb
call bdos
cp 255 ;flag for no match
jp z,nomore
;A has directory code
;file name is at buffer+1+32*A
ld hl,buffer+1
ld de,32
again: and a ;to set z flag
jp z,gotit
dec a
add hl,de
jp again
gotit: ld de,(psave) ;address of dBase string
ld bc,11 ;length of name+extention
ldir ;move it into the string
ret
nomore: ld hl,empty ;no data message
ld de,(psave)
ld bc,11
ldir
ret
end
After assembly, (with M80) the HEX file is created by linking
such that,the laod address is A400H (41984, above the limit of
memory used by dBase) as follows:
L80 /PA400,DIREAD,DIREAD/X/N/E
This is a pretty primative example, but it does exercise the
dBase machine language interface functions.
If anybody has any information regarding the defaults,
I would also be interested.
Bruce Conroy (
[email protected])
