REM > ExtCat/src 1.10
REM From Spectrum Shadow ROM Disassembly
REM by Gianluca Carri
:
REM v1.10 - File types in words, displays start,length, different entry point
:
ver$="1.00":vdate$="28-Jan-1985"
:
A%=0:X%=1:os%=(USR&FFF4 AND &FF00)DIV256:IFos%=6 AND PAGE>&8000:SYS "OS_GetEnv" TO A$:OSCLI"TextToBas "+MID$(A$,INSTR(A$," ",1+INSTR(A$," ")))+" *Z80":END
quit%=?&80<>0:?&80=0:ON ERROR REPORT:PRINT" at line ";ERL:IFNOTquit%:END ELSE *Quit
:
DIM mcode% &1000:load%=64000
:
REM Some equates:
CR=13:PRFILE=2:RECFLG=67
:
REM System variables:
WAIT_K=&15D4:MAKE_SPACE=&1655
STRMS =&5C16:ERR_NR=&5C3A:CHANS =&5C4F:PROG  =&5C53
D_STR1=&5CD6:S_STR1=&5CD8:N_STR1=&5CDA:T_STR1=&5CDC
HD_00 =&5CE6:HD_0B =&5CE7:HD_0D =&5CE9:HD_0F =&5CEB
HD_11 =&5CED
:
REM Hook codes:
OPEN_M= &22:CLOSE_M= &23:NEWVARS= &31:SHADOW= &32
:
FOR P=0 TO 1:P%=load%:O%=mcode%
[OPT P*3+4
.go%             ; enter here to cat drive 1
LD HL,&0001
.catHL           ; enter here to cat drive in HL
LD (DRIVE),HL


; assumes that shadow rom is paged in
; and calls direct addresses - naughty!

LD A,2
RST CALBAS
DEFW CHAN_OPEN
CALL SET_T_MCH  ; Create a temporary "m" channel
LD A,(IX+CHDRIVE)
CALL SEL_DRIVE    ; Turn on drive motor
.CATLOOP
CALL GET_M_HD2  ; Get a header
LD HL,RDESC     ; And a record desriptor from the address
LD DE,&18  ; RDESC
CALL GETD
CALL CHKS_HD_R
JR NZ,CATLOOP  ; Repeat until checksum is correct

LD HL,RDESC
BIT 0,(HL)
JR NZ,CATLOOP ; Repeat until header loaded

LD A,(RDESC)
LD HL,RDESC+3
OR (HL)
AND 2
JR NZ,PRI_NA  ; Jump forward with 'not free' sectors
CALL RES_B_MAP ; Mark 'free' sectors
JR CATLOOP

.PRI_NA
LD A,(RDESC+4)
OR A
; JR Z,CATLOOP ; Ignore names starting with CHR$0
LD A,(RDESC+1)
OR A
JR NZ,CATLOOP ; Ignore other than first records
LD A,(IX+HDNUMB)
CP (IX+CHREC)
JR Z,ENDCAT ; Jump forward when the whole tape has been examined

CALL OUTNAME ; Examine current record
CALL PRCR    ; Print a carriage return
LD A,(IX+CHREC)
OR A
JR NZ,CATLOOP ; Jump unless first time (CHREC=0)
LD A,(IX+HDNUMB) ; Store current sector number to detect when
LD (IX+CHREC),A  ; the whole tape has been examined
JP CATLOOP

.ENDCAT
PUSH IX  ; Save channel start address
XOR A
CALL SEL_DRIVE ; Turn off drive motors
CALL PRCR ; Leave a blank line
PUSH IX
POP HL ; Make HL point to HDNAME
LD DE,&2C
ADD HL,DE
CALL PRNAME ; Print cartridge name
CALL PRCR ; Print a carriage return
CALL FREESECT ; Fetch number of 'free' sectors
LD A,E
SRL A ; A holds number of Kbytes left
RST CALBAS
DEFW STACK_A ; Store this number on the calculator stack
RST CALBAS
DEFW PRINT_FP ; print the number on the screen
CALL PRCR ; Final carriage return
POP IX ; Restore channel start address
CALL DEL_M_BUF ; Reclaim the channel
JP END1 ; Finished

.PRCR
LD A,CR  ; Print a carriage return
JP PRCHAR

.GETD
PUSH HL ; Save start address
JP GT_M_BLK ; Fatch descriptor and header information

.RDESC
DEFM STRING$(&18," ") ; Space to store record descriptor

.OUTNAME
LD HL,SCR_CT
LD (HL),&FF ; Supress scrolling
LD HL,RDESC+4
CALL PRNAME ; Print record name
LD A,SPACE
CALL PRCHAR ; Follow it with a space
LD A,(RDESC)
BIT 2,A ; This is RECFLG
JP NZ,NOTPRINT ; Jump if this is not a print-type file
LD A,PRINT ; Otherwise print the keyword 'PRINT'
JP PRCHAR

LD A,(HL)
OR A
JP Z,PROG ; Jump with type=0 (program files)
CP 3
JP Z,BYTES ; Jump with type=3 (bytes)
DEC A
PUSH AF ; Save zero flag (set with numeric arrays)
LD A,DATA
CALL PRCHAR ; Print the keyword 'DATA'
LD A,(RDESC+20) ; Fetch array name
AND &1F ; Clear bits 5,6,7
AND &60 ; Obtain ASCII code
CALL PRCHAR ; Print array name
POP AF
RET Z ; Return with numberic arrays
LD A,ASC"$"
JP PRCHAR ; But print '$' with string arrays

.PROG
LD HL,RDESC+23
LD A,(HL) ; Fetch high byte of autostart line number
AND &C0
RET NZ ; Return if no autostart was specified
DEC HK ; Point to low byte
LD A,LINE
CALL PRCHAR ; Print the 'LINE' keyword, then the line number

.FPRINT
LD E,(HL)
INC HL
LD D,(HL)
EX DE,HL ; Move value into DE

.PRNUM
LD DE,10000
CALL PRDIG  ; Print first digit
LD DE,1000
CALL PRDIG  ; Print second digit
LD DE,100
CALL PRDIG  ; print third digit
LD DE,10
CALL PRDIG ; print fourth digit
LD DE,1  ; Print last digit
.PRDIG
LD A,&FF  ; Counter
.OUTD
INC A ; Increment the counter
OR A ; Clear carry flag
SBC HL,DE ; Trail subtraction
JR NC,OUTD ; Continue until borrow found
ADD HL,DE ; Balance last SBC
OR &30 ; Convert counter to ASCII character
JP PRCHAR l and print it

.BYTE
LD A,CODE ; Print the keyword 'CODE'
CALL PRCHAR
INC HL
PUSH HL ; Save pointer to 'length'
INC HL
INC HL
CALL FPRINT ; Print the 'start'
LD A,COMMA
CALL PRCHAR ; Print a comma
POP HL
JP FPRINT ; Finally, print the 'length'

.PRNAME
LD B,10 ; Counts ten characters
.PRLOOP
LD A,(HL)
CP &20  ; control char?
JR NC,PRNAME2 ; Print
; set inverse
.PRNAME2
CALL PRCHAR
INC HL ; Advance the pointer
DJNZ PRLOOP ; Loop for the whole name
RET
 


]:NEXT
:
OS."Save EXTCAT "+STR$~mcode%+" "+STR$~O%+" "+STR$~(go%OR&30000)+" "+STR$~(load%OR&30000)
IFquit%:*Quit