*************************************************************************
* *
* OSFIND ENTRY *
* file handling *
* *
*************************************************************************
;on entry A determines Action Y may contain file handle or
;X/Y point to filename terminated by &0D in memory
;A=0 closes file in channel Y if Y=0 closes all files
;A=&40 open a file for input (reading) X/Y points to filename
;A=&80 open a file for output (writing) X/Y points to filename
;A=&C0 open a file for input and output (random access)
;ON EXIT Y=0 if no file found else Y=channel number in use for file
;save A X and Y
F3CA STA &BC ;file status or temporary store
F3CC TXA ;A=X
F3CD PHA ;save X on stack
F3CE TYA ;A=Y
F3CF PHA ;save Y on stack
F3D0 LDA &BC ;file status or temporary store
F3D2 BNE &F3F2 ;if A is non zero open a file via F3F2
************ close a file ***********************************************
F3D4 TYA ;A=Y
F3D5 BNE &F3E3 ;if A<> 0 close specified file else close them all
F3D7 JSR &E275 ;close spool/exec files via OSBYTE 77
F3DA JSR &F478 ;tidy up
F3DD LSR &E2 ;CFS status byte is shifted left and right to zero
F3DF ASL &E2 ;bit 0
F3E1 BCC &F3EF ;and if carry clear no input file was open so F3EF
F3E3 LSR ;A contains file handle so shift bit 0 into carry
F3E4 BCS &F3DD ;if carry set close input file
F3E6 LSR ;else shift bit 1 into carry
F3E7 BCS &F3EC ;if carry set close output file
F3E9 JMP &FBB1 ;else report 'Channel Error' as CFS can only support
;1 input and 1 output file
F3EC JSR &F478 ;tidy up
F3EF JMP &F471 ;and exit
************ OPEN A FILE ************************************************
F3F2 JSR &F25A ;get filename from BUFFER
F3F5 BIT &BC ;file status or temporary store
F3F7 BVC &F436 ;check A at input if bit 6 not set its an output file
********* Input files +**************************************************
F3F9 LDA #&00 ;else its an input file
F3FB STA &039E ;BGET buffer offset for next byte
F3FE STA &03DD ;Expected BGET file block number lo
F401 STA &03DE ;expected BGET file block number hi
F404 LDA #&3E ;A=&3E
F406 JSR &F33D ;CFS status =CFS status AND A
F409 JSR &FB1A ;claim serial system and set OPTions
F40C PHP ;save flags on stack
F40D JSR &F631 ;search for file
F410 JSR &F6B4 ;check protection bit of block status and respond
F413 PLP ;get back flags
F414 LDX #&FF ;X=&FF increment to 0 on next instruction
F416 INX ;X=X+1
F417 LDA &03B2,X ;get file name and
F41A STA &03A7,X ;store as BGET filename
F41D BNE &F416 ;until end of filename
F41F LDA #&01 ;A=1 to show file open
F421 JSR &F344 ;set status bits from A
F424 LDA &02EA ;CFS currently resident file block length lo
F427 ORA &02EB ;CFS currently resident file block length hi
F42A BNE &F42F ;if block length is 0
F42C JSR &F342 ;set CFS status bit 3 (EOF reached)
;else
F42F LDA #&01 ;A=1
F431 ORA &0247 ;filing system flag 0=CFS 2=RFS
F434 BNE &F46F ;and exit after restoring registers
******************* open an output file***********************************
F436 TXA ;A=X
F437 BNE &F43C ;if X=0 then zero length filename so
F439 JMP &EA8F ;Bad String error
F43C LDX #&FF ;X=&FF
F43E INX ;X=X+1
;copy sought filename to header block
F43F LDA &03D2,X ;sought filename
F442 STA &0380,X ;BPUT file header block
F445 BNE &F43E ;until A=0 end of filename
F447 LDA #&FF ;A=&FF
F449 LDX #&08 ;X=8
F44B STA &038B,X ;set 38C/93 to &FF
F44E DEX ;X=X-1
F44F BNE &F44B ;
F451 TXA ;A=X=0
F452 LDX #&14 ;X=14
F454 STA &0380,X ;BPUT file header block
F457 INX ;X=X+1
F458 CPX #&1E ;this zeros 394/D
F45A BNE &F454 ;
F45C ROL &0397 ;
F45F JSR &FB27 ;Set cassette optionsinto (BB),set C7=6
;claim serial system for cassette
F462 JSR &F934 ;prompt to start recording
F465 JSR &FAF2 ;enable second processor and reset serial system
F468 LDA #&02 ;A=2
F46A JSR &F344 ;set status bits from A
F46D LDA #&02 ;A=2
F46F STA &BC ;file status or temporary store
F471 PLA ;get back A
F472 TAY ;Y=A
F473 PLA ;get back A
F474 TAX ;X=A
F475 LDA &BC ;file status or temporary store
F477 RTS ;return
;
F478 LDA #&02 ;A=2 clearing all but bit 1 of status byte
F47A AND &E2 ;CFS status byte, with output file open
F47C BEQ &F477 ;if file not open then exit
F47E LDA #&00 ;else A=0
F480 STA &0397 ;setting block length to current value of BPUT offset
F483 LDA #&80 ;A=&80
F485 LDX &039D ;get BPUT buffer ofset
F488 STX &0396 ;setting block length to current value of BPUT offset
F48B STA &0398 ;mark current block as last
F48E JSR &F496 ;save block to tape
F491 LDA #&FD ;A=&FD
F493 JMP &F33D ;CFS status =CFS status AND A
*********** SAVE BLOCK TO TAPE ********************************************
F496 JSR &FB1A ;claim serial system and set OPTions
F499 LDX #&11 ;X=11
F49B LDA &038C,X ;copy header block from 38C-39D
F49E STA &03BE,X ;to 3BE/DF
F4A1 DEX ;X=X-1
F4A2 BPL &F49B ;
;X=&FF
F4A4 STX &B2 ;current load address high word
F4A6 STX &B3 ;current load address high word
F4A8 INX ;X=X+1, (X=0)
F4A9 STX &B0 ;current load address lo byte set to &00
F4AB LDA #&09 ;A=9 to set current load address at &900
F4AD STA &B1 ;current load address
F4AF LDX #&7F ;X=&7F
F4B1 JSR &FB81 ;copy from 301/C+X to 3D2/C sought filename
F4B4 STA &03DF ;copy of last read block flag
F4B7 JSR &FB8E ;switch Motor On
F4BA JSR &FBE2 ;set up CFS for write operation
F4BD JSR &F7EC ;write block to Tape
F4C0 INC &0394 ;block number lo
F4C3 BNE &F4C8 ;
F4C5 INC &0395 ;block number hi
F4C8 RTS ;return
*************************************************************************
* *
* *
* OSBGET get a byte from a file *
* *
* *
*************************************************************************
;on ENTRY Y contains channel number
;on EXIT X and Y are preserved C=0 indicates valid character
; A contains character (or error) A=&FE End Of File
;push X and Y
F4C9 TXA ;A=X
F4CA PHA ;save A on stack
F4CB TYA ;A=Y
F4CC PHA ;save A on stack
F4CD LDA #&01 ;A=1
F4CF JSR &FB9C ;check conditions for OSBGET are OK
F4D2 LDA &E2 ;CFS status byte
F4D4 ASL ;shift bit 7 into carry (EOF warning given)
F4D5 BCS &F523 ;if carry set F523
F4D7 ASL ;shift bit 6 into carry
F4D8 BCC &F4E3 ;if clear EOF not reached F4E3
F4DA LDA #&80 ;else A=&80 setting bit 7 of status byte EOF warning
F4DC JSR &F344 ;set status bits from A
F4DF LDA #&FE ;A=&FE
F4E1 BCS &F51B ;if carry set F51B
F4E3 LDX &039E ;BGET buffer offset for next byte
F4E6 INX ;X=X+1
F4E7 CPX &02EA ;CFS currently resident file block length lo
F4EA BNE &F516 ;read a byte
;else
F4EC BIT &02EC ;block flag of currently resident block
F4EF BMI &F513 ;if bit 7=1 this is the last block so F513 else
F4F1 LDA &02ED ;last character of currently resident block
F4F4 PHA ;save A on stack
F4F5 JSR &FB1A ;claim serial system and set OPTions
F4F8 PHP ;save flags on stack
F4F9 JSR &F6AC ;read in a new block
F4FC PLP ;get back flags
F4FD PLA ;get back A
F4FE STA &BC ;file status or temporary store
F500 CLC ;clear carry flag
F501 BIT &02EC ;block flag of currently resident block
F504 BPL &F51D ;if not last block (bit 7=0)
F506 LDA &02EA ;CFS currently resident file block length lo
F509 ORA &02EB ;CFS currently resident file block length hi
F50C BNE &F51D ;if block size not 0 F51D else
F50E JSR &F342 ;set CFS status bit 6 (EOF reached)
F511 BNE &F51D ;goto F51D
F513 JSR &F342 ;set CFS status bit 6 (EOF reached)
F516 DEX ;X=X-1
F517 CLC ;clear carry flag
F518 LDA &0A00,X ;read byte from cassette buffer
F51B STA &BC ;file status or temporary store
F51D INC &039E ;BGET buffer offset for next byte
F520 JMP &F471 ;exit via F471
F523 BRK ;
F524 DB &DF ;error number
F525 DB 'EOF' ;
F528 BRK ;
*************************************************************************
* *
* *
* OSBPUT WRITE A BYTE TO FILE *
* *
* *
*************************************************************************
;ON ENTRY Y contains channel number A contains byte to be written
F529 STA &C4 ;store A in temorary store
F52B TXA ;and stack X and Y
F52C PHA ;save on stack
F52D TYA ;A=Y
F52E PHA ;save on stack
F52F LDA #&02 ;A=2
F531 JSR &FB9C ;check conditions necessary for OSBPUT are OK
F534 LDX &039D ;BPUT buffer offset for next byte
F537 LDA &C4 ;get back original value of A
F539 STA &0900,X ;Cassette buffer
F53C INX ;X=X+1
F53D BNE &F545 ;if not 0 F545, otherwise buffer is full so
F53F JSR &F496 ;save block to tape
F542 JSR &FAF2 ;enable second processor and reset serial system
F545 INC &039D ;BPUT buffer offset for next byte
F548 LDA &C4 ;get back A
F54A JMP &F46F ;and exit
*************************************************************************
* *
* *
* OSBYTE 139 Select file options *
* *
* *
*************************************************************************
;ON ENTRY Y contains option value X contains option No. see *OPT X,Y
;this applies largely to CFS LOAD SAVE CAT and RUN
;X=1 is message switch
; Y=0 no messages
; Y=1 short messages
; Y=2 gives detailed information on load and execution addresses
;X=2 is error handling
; Y=0 ignore errors
; Y=1 prompt for a retry
; Y=2 abort operation
;X=3 is interblock gap for BPUT# and PRINT#
; Y=0-127 set gap in 1/10ths Second
; Y > 127 use default values
F54D TXA ;A=X
F54E BEQ &F57E ;if A=0 F57E
F550 CPX #&03 ;if X=3
F552 BEQ &F573 ;F573 to set interblock gap
F554 CPY #&03 ;else if Y>2 then BAD COMMAND error
F556 BCS &F55E ;
F558 DEX ;X=X-1
F559 BEQ &F561 ;i.e. if X=1 F561 message control
F55B DEX ;X=X-1
F55C BEQ &F568 ;i.e. if X=2 F568 error response
F55E JMP &E310 ;else E310 to issue Bad Command error
*********** message control *********************************************
F561 LDA #&33 ;to set lower two bits of each nybble as mask
F563 INY ;Y=Y+1
F564 INY ;Y=Y+1
F565 INY ;Y=Y+1
F566 BNE &F56A ;goto F56A
*********** error response *********************************************
F568 LDA #&CC ;setting top two bits of each nybble as mask
F56A INY ;Y=Y+1
F56B AND &E3 ;clear lower two bits of each nybble
F56D ORA &F581,Y ;or with table value
F570 STA &E3 ;store it in &E3
F572 RTS ;return
;setting of &E3
;
;lower nybble sets LOAD options
;upper sets 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
***********set interblock gap *******************************************
F573 TYA ;A=Y
F574 BMI &F578 ;if Y>127 use default values
F576 BNE &F57A ;if Y<>0 skip next instruction
F578 LDA #&19 ;else A=&19
F57A STA &03D1 ;sequential block gap
F57D RTS ;return
;
F57E TAY ;Y=A
F57F BEQ &F56D ;jump to F56D
*********** DEFAULT OPT VALUES TABLE ************************************
F581 DB &A1 ;%1010 0001
F582 DB &00 ;%0000 0000
F583 DB &22 ;%0010 0010
F584 DB &11 ;%0001 0001
F585 DB &00 ;%0000 0000
F586 DB &88 ;%1000 1000
F587 DB &CC ;%1100 1100
F588 DEC &C0 ;filing system buffer flag
F58A LDA &0247 ;filing system flag 0=CFS 2=RFS
F58D BEQ &F596 ;if CFS F596
F58F JSR &EE51 ;read RFS data rom or Phrom
F592 TAY ;Y=A
F593 CLC ;clear carry flag
F594 BCC &F5B0 ;jump to F5B0
F596 LDA &FE08 ;ACIA status register
F599 PHA ;save A on stack
F59A AND #&02 ;clear all but bits 0,1 A=(0-3)
F59C BEQ &F5A9 ;if 0 F5A9 transmit data register full or RDR empty
F59E LDY &CA ;
F5A0 BEQ &F5A9 ;
F5A2 PLA ;get back A
F5A3 LDA &BD ;character temporary storage
F5A5 STA &FE09 ;ACIA transmit data register
F5A8 RTS ;return
;
F5A9 LDY &FE09 ;read ACIA recieve data register
F5AC PLA ;get back A
F5AD LSR ;bit 2 to carry (data carrier detect)
F5AE LSR ;
F5AF LSR ;
F5B0 LDX &C2 ;progress flag
F5B2 BEQ &F61D ;if &C2=0 exit
F5B4 DEX ;X=X-1
F5B5 BNE &F5BD ;if &C2>1 then F5BD
F5B7 BCC &F61D ;else if carrier tone from cassette detected exit
F5B9 LDY #&02 ;Y=2
F5BB BNE &F61B ;
F5BD DEX ;X=X-1
F5BE BNE &F5D3 ;if &C2>2
F5C0 BCS &F61D ;if carrier tone from cassette not detected exit
F5C2 TYA ;A=Y
F5C3 JSR &FB78 ;set (BE/C0) to 0
F5C6 LDY #&03 ;Y=3
F5C8 CMP #&2A ;is A= to synchronising byte &2A?
F5CA BEQ &F61B ;if so F61B
F5CC JSR &FB50 ;control cassette system
F5CF LDY #&01 ;Y=1
F5D1 BNE &F61B ;goto F61B
F5D3 DEX ;X=X-1
F5D4 BNE &F5E2 ;if &C2>3
F5D6 BCS &F5DC ;
F5D8 STY &BD ;get character read into Y
F5DA BEQ &F61D ;if 0 exit via F61D
F5DC LDA #&80 ;else A=&80
F5DE STA &C0 ;filing system buffer flag
F5E0 BNE &F61D ;and exit
F5E2 DEX ;X=X-1
F5E3 BNE &F60E ;if &C2>4 F60E
F5E5 BCS &F616 ;if carry set F616
F5E7 TYA ;A=Y
F5E8 JSR &F7B0 ;perform CRC
F5EB LDY &BC ;file status or temporary store
F5ED INC &BC ;file status or temporary store
F5EF BIT &BD ;if bit 7 set this is the last byte read
F5F1 BMI &F600 ;so F600
F5F3 JSR &FBD3 ;check if second processor file test tube prescence
F5F6 BEQ &F5FD ;if return with A=0 F5FD
F5F8 STX &FEE5 ;Tube FIFO3
F5FB BNE &F600 ;
F5FD TXA ;A=X restore value
F5FE STA (&B0),Y ;store to current load address
F600 INY ;Y=Y+1
F601 CPY &03C8 ;block length
F604 BNE &F61D ;exit
F606 LDA #&01 ;A=1
F608 STA &BC ;file status or temporary store
F60A LDY #&05 ;Y=5
F60C BNE &F61B ;exit
F60E TYA ;A=Y
F60F JSR &F7B0 ;perform CRC
F612 DEC &BC ;file status or temporary store
F614 BPL &F61D ;exit
F616 JSR &FB46 ;reset ACIA
F619 LDY #&00 ;Y=0
F61B STY &C2 ;progress flag
F61D RTS ;return
*************************************************************************
* *
* FSCV xx - check for end of file *
* *
*************************************************************************
;
F61E PHA ;save A on stack
F61F TYA ;A=Y
F620 PHA ;save Y on stack
F621 TXA ;A=X to put X into Y
F622 TAY ;Y=A
F623 LDA #&03 ;A=3
F625 JSR &FB9C ;confirm file is open
F628 LDA &E2 ;CFS status byte
F62A AND #&40 ;
F62C TAX ;X=A
F62D PLA ;get back A
F62E TAY ;Y=A
F62F PLA ;get back A
F630 RTS ;return
;
F631 LDA #&00 ;A=0
F633 STA &B4 ;current block no. lo
F635 STA &B5 ;current block no. hi
F637 LDA &B4 ;current block no. lo
F639 PHA ;save A on stack
F63A STA &B6 ;next block no. lo
F63C LDA &B5 ;current block no. hi
F63E PHA ;save A on stack
F63F STA &B7 ;next block no. hi
F641 JSR &FA46 ;print message following call
F644 DB 'Searching';
F64C DB &0D ;newline
F64E BRK ;
F64F LDA #&FF ;A=&FF
F651 JSR &F348 ;read data from CFS/RFS
F654 PLA ;get back A
F655 STA &B5 ;current block no. hi
F657 PLA ;get back A
F658 STA &B4 ;current block no. lo
F65A LDA &B6 ;next block no. lo
F65C ORA &B7 ;next block no. hi
F65E BNE &F66D ;
F660 STA &B4 ;current block no. lo
F662 STA &B5 ;current block no. hi
F664 LDA &C1 ;checksum result
F666 BNE &F66D ;
F668 LDX #&B1 ;current load address
F66A JSR &FB81 ;copy from 301/C+X to 3D2/C sought filename
F66D LDA &0247 ;filing system flag 0=CFS 2=RFS
F670 BEQ &F685 ;if cassette F685
F672 BVS &F685 ;
F674 BRK ;
F675 DB &D6 ;Error number
F676 DB 'File Not found'
F684 BRK ;
F685 LDY #&FF ;Y=&FF
F687 STY &03DF ;copy of last read block flag
F68A RTS ;return
;