OS SERIES 9
GEOFF COX
*************************************************************************
*                                                                       *
*       OSBYTE 140  *TAPE                                               *
*       selects TAPE filing system                                      *
*                                                                       *
*       OSBYTE 141  *ROM                                                *
*       selects ROM filing system                                       *
*                                                                       *
*************************************************************************

F135	EOR #&8C    ;if it's *TAPE A=0 *ROM A=1
F137	ASL         ;double it
F138	STA &0247   ;store it in filing system flag store
F13B	CPX #&03    ;if X>=3 C set X=3 Z set
F13D	JMP &F14B   ;

******** set cassette options *******************************************
    	;called after BREAK etc
    	;lower nybble sets sequential access
    	;upper sets load and save options
    	
    	;0000   Ignore errors,          no messages
    	;0001   Abort if error,         no messages
    	;0010   Retry after error,      no messages
    	;1000   Ignore error            short messages
    	;1001   Abort if error          short messages
    	;1010   Retry after error       short messages
    	;1100   Ignore error            long messages
    	;1101   Abort if error          long messages
    	;1110   Retry after error       long messages


F140	PHP         ;save flags
F141	LDA #&A1    ;set sequential access abort if error, no messages
F143	STA &E3     ;set load/save retry if error, short messages
F145	LDA #&19    ;set interblock gap
F147	STA &03D1   ;and store it
F14A	PLP         ;get back flags

F14B	PHP         ;push flags
F14C	LDA #&06    ;get close files command to FSCV
F14E	JSR &E031   ;and gosub OSFSC
F151	LDX #&06    ;
F153	PLP         ;get back flags
F154	BEQ &F157   ;if Z set earlier
F156	DEX         ;do not decrement X
F157	STX &C6     ;set current baud rate X=5 300 baud X=6 1200 baud

********* reset FILEV,ARGSV,BGETV,BPUTV,GBPBV,FINDV,FSCV ******************
**********   to F27D, F18E, F4C9, F529, FFA6, F3CA, F1B1 ******************

F159	LDX #&0E    ;RESET VECTORS FOR FILE RELATED OPERATIONS
F15B	LDA &D951,X ;
F15E	STA &0211,X ;
F161	DEX         ;
F162	BNE &F15B   ;

F164	STX &C2     ;&C2=0 PROGRESS FLAG
F166	LDX #&0F    ;set X to make Rom service call &F claim vectors!



*************************************************************************
*                                                                       *
*       OSBYTE 143                                                      *
*       Pass service commands to sideways Roms                          *
*                                                                       *
*************************************************************************
    	    ;on entry X=command number

F168	LDA &F4     ;get current Rom number
F16A	PHA         ;store it
F16B	TXA         ;command in A
F16C	LDX #&0F    ;set X=15

    	            ;send commands loop
F16E	INC &02A1,X ;read bit 7 on rom map (no rom has type 254 &FE)
F171	DEC &02A1,X ;
F174	BPL &F183   ;if not set (+ve result)
F176	STX &F4     ;else store rom number in &F4
F178	STX &FE30   ;switch in paged ROM
F17B	JSR &8003   ;and jump tp service entry
F17E	TAX         ;on exit put A in X
F17F	BEQ &F186   ;if 0 (command recognised by ROM) reset roms & exit
F181	LDX &F4     ;else point to next lower rom
F183	DEX         ;
F184	BPL &F16E   ;and go round loop again

F186	PLA         ;get back original Rom number
F187	STA &F4     ;store it in Ram copy
F189	STA &FE30   ;select original page
F18C	TXA         ;put X back in A
F18D	RTS         ;and return



*************************************************************************
*                                                                       *
*       CFS OSARGS entry point                                          *
*
*************************************************************************

F18E	ORA #&00    ;is A=00
F190	BNE &F1A2   ;if not return
F192	CPY #&00    ;is Y=0
F194	BNE &F1A2   ;if not return
F196	LDA &C6     ;else get current baud rate and zero bit 2
F198	AND #&FB    ;C6=5 becomes 1, 6 becomes 2
F19A	ORA &0247   ;if cassette selected A=0 else A=2
F19D	ASL         ;multiply by 2
F19E	ORA &0247   ;Or it again
F1A1	LSR         ;divide by 2
F1A2	RTS         ;return cassette =0
    	
*************************************************************************
*                                                                       *
*       FSC     VECTOR  TABLE                                           *
*                                                                       *
*************************************************************************

F1A3	DB  4C,F5   ; *OPT            (F54C)
F1A5	DB  1D,F6   ; check EOF       (F61D)
F1A7	DB  04,F3   ; */              (F304)
F1A9	DB  0F,E3   ; unknown command (E30F)
F1AB	DB  04,F3   ; *RUN            (F304)
F1AD	DB  2A,F3   ; *CAT            (F32A)
F1AF	DB  74,E2   ; osbyte 77       (E274)


*************************************************************************
*       Filing System control entry     OSFSC                           *
*       Entry via 021E FSCV                                             *
*       A= index 0 to 7                                                 *
*************************************************************************
    	;on entry A is reason code
    	;A=0    A *OPT command has been used X & Y are the 2 parameters
    	;A=1    EOF is being checked, on entry  X=File handle
    	                          on Exit X=FF = EOF exists else 00
    	;A=2    A */ command has been used *RUN the file
    	;A=3    An unrecognised OS command has ben used X,Y point at command
    	;A=4    A *RUN command has been used X,Y point at filename
    	;A=5    A *CAT cammand has been issued X,Y point to rest of command
    	;A=6    New filing system about to take over, close SPOOL & EXEC files
    	;A=7    Return in X and Y lowest and highest file handle used
    	;A=8    OS about to process *command

F1B1	CMP #&07    ;if A>6
F1B3	BCS &F1A2   ;goto F1A2 (RTS)
F1B5	STX &BC     ;else save X
F1B7	ASL         ;A=A*2
F1B8	TAX         ;X=A to get offset
F1B9	LDA &F1A4,X ;get hi byte of address
F1BC	PHA         ;push it
F1BD	LDA &F1A3,X ;get lo byte of address
F1C0	PHA         ;push it
F1C1	LDX &BC     ;get back X
F1C3	RTS         ;this now jumps to the address got from the table +1
    	            ;the next RTS takes us back to CLI



*************************************************************************
*                                                                       *
*       LOAD FILE                                                       *
*                                                                       *
*************************************************************************
    	
F1C4	PHP         ;save flags on stack
F1C5	PHA         ;save A on stack
F1C6	JSR &FB27   ;Set cassette optionsinto (BB),set C7=6
    	            ;claim serial system for cassette
F1C9	LDA &03C2   ;execution address LO
F1CC	PHA         ;save A on stack
F1CD	JSR &F631   ;search for file
F1D0	PLA         ;get back A
F1D1	BEQ &F1ED   ;if A=0 F1ED
F1D3	LDX #&03    ;else X=3
F1D5	LDA #&FF    ;A=&FF
F1D7	PHA         ;save A on stack
F1D8	LDA &03BE,X ;get load address
F1DB	STA &B0,X   ;store it as current load address
F1DD	PLA         ;get back A
F1DE	AND &B0,X   ;
F1E0	DEX         ;X=X-1
F1E1	BPL &F1D7   ;until all 4 bytes copied

F1E3	CMP #&FF    ;if all bytes contain don't contain &FF
F1E5	BNE &F1ED   ;continue
F1E7	JSR &FAE8   ;else sound bell, reset ACIA & motor off
F1EA	JMP &E267   ;'Bad Address' error

F1ED	LDA &03CA   ;block flag
F1F0	LSR         ;set carry from bit 0
F1F1	PLA         ;get back A
F1F2	BEQ &F202   ;if A=0 F202
F1F4	BCC &F209   ;if carry clear F209


*************** LOCKED FILE ROUTINE *************************************

F1F6	JSR &FAF2   ;enable second processor and reset serial system

F1F9	BRK         ;
F1FA	DB  &E5     ;error number
F1FC	'Locked'        ;
F201	BRK         ;


F202	BCC &F209   ;if carry clear F209
F204	LDA #&03    ;else A=3
F206	STA &0258   ;store to cause ESCAPE disable and memory
    	            ;clear on break

F209	LDA #&30    ;
F20B	AND &BB     ;current OPTions
F20D	BEQ &F213   ;if options and #&30 =0 ignore error condition is set
F20F	LDA &C1     ;else get checksum result
F211	BNE &F21D   ;and if not 0 F21D

F213	TYA         ;A=Y
F214	PHA         ;save A on stack
F215	JSR &FBBB   ;read from second processor if present
F218	PLA         ;get back A
F219	TAY         ;Y=A
F21A	JSR &F7D5   ;reset flags and check block length
F21D	JSR &F9B4   ;load file from tape
F220	BNE &F255   ;if not found return to search
F222	JSR &FB69   ;increment current block number
F225	BIT &03CA   ;block flag
F228	BMI &F232   ;if bit 7=1 then this is last block so F232
F22A	JSR &F96A   ;else increment current load address
F22D	JSR &F77B   ;read block header
F230	BNE &F209   ;and goto F209

******** store data in OSFILE parameter block ***************************

F232	LDY #&0A    ;Y=&0A
F234	LDA &CC     ;file length counter lo
F236	STA (&C8),Y ;OSFILE parameter  block
F238	INY         ;Y=Y+1
F239	LDA &CD     ;file length counter hi
F23B	STA (&C8),Y ;OSFILE parameter  block
F23D	LDA #&00    ;A=0
F23F	INY         ;Y=Y+1
F240	STA (&C8),Y ;OSFILE parameter  block
F242	INY         ;Y=Y+1
F243	STA (&C8),Y ;OSFILE parameter  block
F245	PLP         ;get back flags
F246	JSR &FAE8   ;bell, reset ACIA & motor
F249	BIT &BA     ;current block flag
F24B	BMI &F254   ;return
F24D	PHP         ;save flags on stack
F24E	JSR &FA46   ; print message following call (in this case NEWLINE!)
F251	DB  &0D,&00 ;message
F254	RTS         ;return
    	;
************RETRY AFTER A FAILURE ROUTINE *******************************

F255	JSR &F637   ;search for a specified block
F258	BNE &F209   ;goto F209



*********** Read Filename using Command Line Interpreter ****************

;filename pointed to by X and Y

F25A	STX &F2     ;OS filename/command line pointer lo
F25C	STY &F3     ;OS filename/command line pointer
F25E	LDY #&00    ;Y=0
F260	JSR &EA1D   ;initialise string
F263	LDX #&00    ;X=0
F265	JSR &EA2F   ;GSREAD call
F268	BCS &F277   ;if end of character string F277
F26A	BEQ &F274   ;if 0 found F274
F26C	STA &03D2,X ;else store character in CFS filename area
F26F	INX         ;X=X+1
F270	CPX #&0B    ;if X<>11
F272	BNE &F265   ;then read next
F274	JMP &EA8F   ;else Bad String error



************* terminate Filename ****************************************

F277	LDA #&00    ;terminate filename with 0
F279	STA &03D2,X ;
F27C	RTS         ;return




*************************************************************************
*                                                                       *
*       OSFILE ENTRY                                                    *
*                                                                       *
*       on entry A determines action                                    *
*       A=0     save block of memory as a file                          *
*       A=1     write catalogue info for existing file                  *
*       A=2     write load address only for existing file               *
*       A=3     write execution address only for existing file          *
*       A=4     write attributes only for existing file                 *
*       A=5     Read catalogue info, return file type in A              *
*       A=6     Delete named file                                       *
*       A=&FF   load the named file if lo byte of Exec address=0 use    *
*               address in parameter block else files own load address  *
*       X,Y     point to parameter block                                *
*       bytes   0,1 filename address, 2-5 load,6-9 exec,A-D length or   *
*               start of data for save, 0E End address /attributes      *
*************************************************************************

;parameter block located by XY
;0/1	Address of Filename terminated by &0D
;2/4	Load Address of File
;6/9	Execution Address of File
;A/D	Start address of data for write operations or length of file
;   	for read operations
;E/11   End address of Data; i.e. byte AFTER last byte to be written
;   	or file attributes
;
;On Entry action is determined by value in A
;
;A=0	Save section of memory as named file, write catalogue information
;A=1	Write catalogue information for named file
;A=2	Write the LOAD       address (only) for the named File
;A=3	Write the EXECUTION  address (only) for the named File
;A=4	Write the ATTRIBUTES for the named File
;A=5	Read the named files catalogue information Place file type in A
;A=6	Delete the named file
;A=&FF  Load the named file and read its catalogue information

F27D	PHA         ;save A on stack
F27E	STX &C8     ;osfile block pointer lo
F280	STY &C9     ;osfile block pointer hi
F282	LDY #&00    ;Y=0
F284	LDA (&C8),Y ;OSFILE parameter  block
F286	TAX         ;X=A
F287	INY         ;Y=Y+1
F288	LDA (&C8),Y ;OSFILE parameter  block
F28A	TAY         ;Y=A
F28B	JSR &F25A   ;get filename from BUFFER
F28E	LDY #&02    ;Y=2

F290	LDA (&C8),Y ;copy parameters to Cassette block at 3BE/C5
F292	STA &03BC,Y ;from LOAD and EXEC address
F295	STA &00AE,Y ;make second copy at B0-B8
F298	INY         ;Y=Y+1
F299	CPY #&0A    ;until Y=10
F29B	BNE &F290   ;

F29D	PLA         ;get back A
F29E	BEQ &F2A7   ;if A=0 F2A7
F2A0	CMP #&FF    ;else if A<>&FF
F2A2	BNE &F254   ;RETURN as cassette has no other options
F2A4	JMP &F1C4   ;load file


************** Save a file **********************************************

F2A7	STA &03C6   ;zero block number
F2AA	STA &03C7   ;zero block number hi

F2AD	LDA (&C8),Y ;OSFILE parameter  block
F2AF	STA &00A6,Y ;store to Zero page copy (&B0 to &B7)
F2B2	INY         ;data start and data end address
F2B3	CPY #&12    ;until Y=18
F2B5	BNE &F2AD   ;
F2B7	TXA         ;A=X
F2B8	BEQ &F274   ;if X=0 no filename found so B274 else BAD STRING error

F2BA	JSR &FB27   ;Set cassette option sinto (BB),set C7=6
    	            ;claim serial system for cassette
F2BD	JSR &F934   ;prompt to start recording

F2C0	LDA #&00    ;A=0
F2C2	JSR &FBBD   ;enable 2nd proc. if present and set up osfile block
F2C5	JSR &FBE2   ;set up CFS for write operation
F2C8	SEC         ;set carry flag
F2C9	LDX #&FD    ;X=&FD

F2CB	LDA &FFB7,X ;set 03C8/A block length and block flag
F2CE	SBC &FFB3,X ;to B4/6-B0/2 the number of pages (blocks) to be
    	            ;saved
F2D1	STA &02CB,X ;
F2D4	INX         ;X=X+1
F2D5	BNE &F2CB   ;

F2D7	TAY         ;Y=A
F2D8	BNE &F2E8   ;if last byte is non zero F2E8 else
F2DA	CPX &03C8   ;compare X with block length
F2DD	LDA #&01    ;A=1
F2DF	SBC &03C9   ;subtract block length hi
F2E2	BCC &F2E8   ;if carry clear F2E8

F2E4	LDX #&80    ;X=&80
F2E6	BNE &F2F0   ;jump F2F0

F2E8	LDA #&01    ;A=1
F2EA	STA &03C9   ;block length hi
F2ED	STX &03C8   ;block length
F2F0	STX &03CA   ;block flag
F2F3	JSR &F7EC   ;write block to Tape
F2F6	BMI &F341   ;return if negative
F2F8	JSR &F96A   ;increment current load address
F2FB	INC &03C6   ;block number
F2FE	BNE &F2C8   ;if not 0 loop back again else
F300	INC &03C7   ;block number hi
F303	BNE &F2C8   ;and loop back again



*************************************************************************
*                                                                       *
*       *RUN    ENTRY                                                   *
*                                                                       *
*************************************************************************

F305	JSR &F25A   ;get filename from BUFFER
F308	LDX #&FF    ;X=&FF
F30A	STX &03C2   ;execution address
F30D	JSR &F1C4   ;load file
F310	BIT &027A   ;&FF if tube present
F313	BPL &F31F   ;so if not present F31F else
F315	LDA &03C4   ;execution address extend
F318	AND &03C5   ;execution address extend
F31B	CMP #&FF    ;if they are NOT both &FF i.e.for base processor
F31D	BNE &F322   ;F322 else
F31F	JMP (&03C2) ; RUN file

F322	LDX #&C2    ;point to execution address
F324	LDY #&03    ;(&03C2)
F326	LDA #&04    ;Tube call 4
F328	JMP &FBC7   ;and issue to Tube to run file


*************************************************************************
*                                                                       *
*       *CAT    ENTRY                                                   *
*                                                                       *
*************************************************************************

    	;CASSETTE OPTIONS in &E2

    	;bit 0  input file open
    	;bit 1  output file open
    	;bit 2,4,5  not used
    	;bit 3  current CATalogue status
    	;bit 6  EOF reached
    	;bit 7  EOF warning given

F32B	LDA #&08    ;A=8
F32D	JSR &F344   ;set status bits from A
F330	JSR &FB27   ;Set cassette options into (BB),set C7=6
    	            ;claim serial system for cassette
F333	LDA #&00    ;A=0
F335	JSR &F348   ;read data from CFS/RFS
F338	JSR &FAFC   ;perform read
F33B	LDA #&F7    ;A=&F7
F33D	AND &E2     ;clear bit 3 of CFS status bit
F33F	STA &E2     ;
F341	RTS         ;return
    	;

F342	LDA #&40    ;set bit 6 of E2 cassette options
F344	ORA &E2     ;
F346	BNE &F33F   ;and Jump F33F



********** search routine ***********************************************

F348	PHA         ;save A on stack
F349	LDA &0247   ;filing system flag 0=CFS 2=RFS
F34C	BEQ &F359   ;if CFS F359 else
F34E	JSR &EE13   ;set current Filing System ROM/PHROM
F351	JSR &EE18   ;get byte from data Romcheck type
F354	BCC &F359   ;if carry clear F359 else
F356	CLV         ;clear overflow flag
F357	BVC &F39A   ;JUMP F39A


*********** cassette routine********************************************

F359	JSR &F77B   ;read block header
F35C	LDA &03C6   ;block number
F35F	STA &B4     ;current block no. lo
F361	LDA &03C7   ;block number hi
F364	STA &B5     ;current block no. hi
F366	LDX #&FF    ;X=&FF
F368	STX &03DF   ;copy of last read block flag
F36B	INX         ;X=X+1
F36C	STX &BA     ;current block flag
F36E	BEQ &F376   ;if  0 F376

F370	JSR &FB69   ;inc. current block no.
F373	JSR &F77B   ;read block header
F376	LDA &0247   ;get filing system flag 0=CFS 2=RFS
F379	BEQ &F37D   ;if CFS F37D
F37B	BVC &F39A   ;if V clear F39A
F37D	PLA         ;get back A
F37E	PHA         ;save A on stack
F37F	BEQ &F3AE   ;if A=0 F3AE
F381	JSR &FA72   ;else check filename header block matches searched Fn
F384	BNE &F39C   ;if so F39C
F386	LDA #&30    ;else A=30 to clear all but bits 4/5 of current OPTions