lst off Ymodem Driver source code for GBBS. orginally by Mike Golazewski or Greg Schaefer

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* lst off *--------------------------------------------------------* * Ymodem Driver source code for GBBS... orginally by * * Mike Golazewski or Greg Schaefer (you choose). Sourced * * (Disassembled) w/ Merlin Pro. * * This file is NOT for public distribution. * * (So Lance doesn't get pissed...Aw poor baby) * *--------------------------------------------------------* ORG $5000 ORG $9E00 CHRGET = $03B1 ;acos get character routine GETBYT = $0380 ;get next byte from segment CHKBYT = $0383 ;check next byte in segment GOBCOM = $0386 ;gobble a comma in segment MOVNAME = $038F ;move filename to acos internal SETOVEC = $03A1 ;set acos output vector to dev # DECOUT = $03A7 ;print a signed decimal # to dev OPEN = $03AD ;open a file using acos CLOSE = $03B0 ;close a file using acos RDBLK = $03B9 ;acos read a block call ACOPTHLO = $03CB ;acos path pointer high part ACOPTHHI = $03CC ;acos path pointer lo part ACOSREF = $03CD ;acos reference number PRINT = $0906 ;print to sysops screen (local) MDMIN = $0E15 ;modem: receive a character MDMOUT = $0E18 ;modem: send a character MDMDCD = $0E1B ;modem: check for carrier loss H9E00 = $9E00 H9E01 = $9E01 H9E02 = $9E02 HA5FF = $A5FF HA600 = $A600 HA640 = $A640 HA642 = $A642 MLI = $BF00 ;prodos MLI dispatch point KEY = $C000 STROBE = $C010 PTRIG = $C070 *---------------------------------------------------------* JSR CHKBYT CMP #$AC ;Is it a comma? BEQ H4F11 ;yes, go send a file JSR GETBYT ;no, skip past the offending character JSR H5174 ;zero out some counters and stuff JMP H4F70 ;abort the xfer RTS H4F11 JSR GOBCOM ;gobble the comma JSR MOVNAME ;move the name to acos's buff's JSR OPEN ;open it using acos BCC H4F1D ;if all is ok, continue RTS ;maybe file missing, return... *---------------------------------------------------------* * Go get some file information for use in the header pack * *---------------------------------------------------------* H4F1D LDA ACOPTHLO STA H522E LDA ACOPTHHI STA H522F JSR MLI ;dispatch the call HEX C4 ;Get File Info call DA H522D ;parameters found here BCC H4F34 ;if everything's ok, continue JMP CLOSE ;otherwise close it, leave H4F34 LDA ACOSREF ;get acos internal file ref # STA H5240 ;store it for parms JSR MLI HEX D1 ;Get EOF call DA H523F ;address of Get EOF parms JSR H5174 ;zero out some locations LDA ACOPTHLO ;get pointer to filename/lo STA $00 ;set up indirect address LDA ACOPTHHI ;get pointer to filename/hi STA $01 ;finish setting up LDY #$00 LDA ($00),Y ;get filename length byte TAX H4F52 INY LDA ($00),Y ;get character in filename STA H4F8C,Y ;store it in the [ ] STA HA5FF,Y ;store it in the header packet DEX BNE H4F52 LDA #$1D ;what's this? STA HA640 LDX #$00 ;move the GFI and Get EOF H4F65 LDA H522D,X ;results to header packet STA HA642,X INX CPX #$17 ;done all? BNE H4F65 ;no, loop H4F70 LDA #$00 STA STROBE ;clear the keyboard strobe STA $24 ;start flush left LDY #$03 ;get output channel JSR SETOVEC ;channel 3, sysop (local) JSR SPRINT ;print this, return after brk H4F7E ASC '[' H4F8C ASC ' ] _ #' BRK LDA BADSEND ;last file check BEQ H4FAA ;if ok, continue JMP H5086 ;close 'em, stop sending H4FAA JSR NAKIN ;wait for a or 'C' (wrong!) * In theory, we should wait for just 'C' or 'CK' for ymodem * But greg decides to do it his own way. BCC SENDHEAD ;if ok, continue.. JMP H5086 ;else, close and stop sending *---------------------------------------------------------* * Send the Header Packet with some file information in it * *---------------------------------------------------------* SENDHEAD LDA #$48 ;print an 'H' for header JSR PRSCRN JSR PRCOUNT ;print # of blocks sent LDA #$01 ;get SOH JSR MDMOUT ;send it out the port LDA BLOCKNUM ;get protocol block # JSR MDMOUT ;send it out the port EOR #$FF ;get complement of block # JSR MDMOUT ;send it out the port LDX #$00 ;start at $a600 H4FCC LDA HA600,X ;get the header packet JSR MDMOUT ;send the byte JSR DOCRC ;compute cumulative CRC for it INX ;next byte CPX #$80 ;done 128 bytes? BNE H4FCC ;no, send another LDA CRCHI ;get CRC Hi part JSR MDMOUT ;send it out the port LDA CRCLO ;get CRC Lo part JSR MDMOUT ;out the port we go JSR ACKIN ;Check for an ACK received BCS SENDHEAD ;ACK not received, resend header LDA HA600 ;block length of 0? (EOT) BNE H4FF3 ;no, send file JMP H5089 ;else, yes, close up and return H4FF3 JSR ACKIN ;wait for another ACK? H4FF6 LDA #$0A ;initialize to 10 retries STA RETRIES ;store counter INC BLOCKNUM ;next xmodem block in series LDA BLKLO ;get blocks sent lo CLC ADC #$08 ;blocks sent=blocks sent+8 STA BLKLO ;store result LDA BLKHI ;continue to make sure we ADC #$00 ;included the carry bit STA BLKHI ;store it also JSR PRCOUNT ;print # of blocks sent (again) LDX #$00 ;lo address of read call LDA #$A6 ;hi address of read call LDY #$08 ;number of 128 byte packets JSR RDBLK ;read 'em BCS H506D ;if error, end of file, close... *---------------------------------------------------------* * Send a Huge, 1024 Byte packet to the othe end with CRC * *---------------------------------------------------------* SEND1024 LDA #$53 ;get an 'S' JSR PRSCRN ;print it for the sysop LDA #$00 ;set up indirect address to STA $00 ;point to $a600 LDA #$A6 STA $01 LDA #$02 ;get an STX JSR MDMOUT ;send it out the port LDA BLOCKNUM ;get current block # JSR MDMOUT ;send it EOR #$FF ;255-block # JSR MDMOUT ;send it LDX #$04 ;send 4 packs of 256 bytes LDY #$00 STY CRCLO ;initialize CRC lo STY CRCHI ;initialize CRC hi H5044 LDA ($00),Y ;get the byte JSR MDMOUT ;send it JSR DOCRC ;compute the cumulative CRC INY ;next byte BNE H5044 ;done 256? no, do some more INC $01 ;yes, next 256 bytes DEX ;are we done with the 4 packs? BNE H5044 ;no, go send some more LDA CRCHI ;get CRC hi JSR MDMOUT ;send it LDA CRCLO ;get CRC lo JSR MDMOUT ;send it JSR ACKIN ;check for an ACK BCC H4FF6 ;ok, send the next 1024 byte pack DEC RETRIES ;count number of times packet sent BNE SEND1024 ;if count <> 10, try again JMP H5086 ;aborted transfer *---------------------------------------------------------* * End of transmission of one file, return to caller... * *---------------------------------------------------------* H506D LDA #$0A ;initialize count for last byte STA RETRIES H5072 LDA #$46 ;get an 'F' (final) JSR PRSCRN ;print it to sysop LDA #$04 ;get an EOT JSR MDMOUT ;send it JSR ACKIN ;wait for an ACK BCC H5086 ;if ok, finish up DEC RETRIES ;no ACK, try again... BNE H5072 ;if retries <> 10, try it again H5086 JSR CLOSE ;otherwise close it, finish up H5089 LDX #$00 ;erase bottom line STX $24 ;horizontal position = flush left LDA #$20 ;print a whole line of spaces H508F JSR PRINT INX CPX #$27 ;done yet? BCC H508F ;nope, more spaces LDX #$0F ;put something consistent H5099 STA H4F8C,X ;over top of the filename DEX BNE H5099 LDA #$00 ;start flush left on return STA $24 LDY #$00 ;output device is #0 JSR SETOVEC RTS ;return to calling program *---------------------------------------------------------* * NAKIN routine gets a , or times out waiting * *---------------------------------------------------------* NAKIN LDA #$57 ;put a 'W' on sysop's screen JSR PRSCRN LDY #$3C H50B0 JSR INPUT ;get a character from the modem CMP #$15 ;is it a ? BEQ H50CF ;yes, return gracefully CMP #$43 ;is it a 'C'? BEQ H50CF ;yes, also return gracefully CMP #$03 ;is it a ???? BEQ H50C6 ;non-fatal error in transmission CMP #$18 ; character, major problems BEQ H50C8 ;uh oh, major type problems DEY ;keep trying BNE H50B0 ;not done yet, try again H50C6 SEC ;either timed out or non-fatal RTS H50C8 LDA #$FF ;fatal transmission error STA BADSEND ;cancel next file transmission SEC RTS H50CF CLC ; received, return properly RTS *---------------------------------------------------------* * ACKIN routine gets an , or times out waiting * *---------------------------------------------------------* ACKIN LDA #$57 ;print a 'W' to sysop JSR PRSCRN LDY #$0A ;10 total for retries STY LASTCHAR H50DB JSR INPUT ;get a character from the modem CMP #$15 ;is it a ? BEQ H50ED ;eww, yes, probably bad block CMP #$43 ;is it a 'C'? BEQ H50ED ;yes, bad block, or sync error CMP #$06 ;is it an ? BEQ H50F4 ;yes, return ok DEY ;none of the above, BNE H50DB ;try again H50ED LDA #$45 ;put an 'E' on the sysop's end JSR PRSCRN SEC ;flag for bad data RTS H50F4 CLC ;data ok, return RTS *---------------------------------------------------------* * Get Input from modem or keyboard... aborts send * *---------------------------------------------------------* INPUT LDA #$00 ;initialize outer loop STA LOOPSML LDA #$64 ;initialize inner loop STA LOOPLRG H5100 BIT PTRIG JSR MDMDCD ;are we still connected? BCC H513A ;no, close everything and return JSR MDMIN ;yes, get a character BCC H511E ;no character to get, branch CMP #$03 ;is it an ETX (End of Text) BNE H5115 ;no, check last character CMP #$18 ;is it a can character BNE H511A ;no, make this the last character H5115 CMP LASTCHAR ;is this the last character? (can) BEQ H513A ;yes, flag send as bad, end it H511A STA LASTCHAR ;no, make this the last character RTS H511E LDA KEY ;check the keyboard BMI H512A ;key pressed? No, next part of loop STA STROBE ;yes, clear strobe CMP #$1B ;is it an ? BEQ H513A ;yes, stop transfer H512A BIT PTRIG ;??? DEC LOOPSML ;take car of inside loop BNE H5100 DEC LOOPLRG ;take care of large loop BNE H5100 ;not done, try some more LDA #$00 ;done, nothing, 1 timeout RTS *---------------------------------------------------------* * Take care of bad send info... abort transfer * *---------------------------------------------------------* H513A CMP #$18 ;is it a can character? BNE H5143 ;no, just go abort it LDA #$FF ;, so mark it as bad send STA BADSEND ;save it H5143 PLA PLA PLA PLA JMP H5086 *---------------------------------------------------------* * Calculate a cumulative CRC-16 from Accumulator * *---------------------------------------------------------* DOCRC PHA EOR CRCHI STA CRCHI TXA PHA LDX #$08 H5155 ASL CRCLO ROL CRCHI BCC H516D LDA CRCHI EOR #$10 STA CRCHI LDA CRCLO EOR #$21 STA CRCLO H516D DEX BNE H5155 PLA TAX PLA RTS *---------------------------------------------------------* * Initialize some locations & counters * *---------------------------------------------------------* H5174 LDA #$00 ;zero out some counters STA BLOCKNUM STA BLKLO STA BLKHI STA CRCLO STA CRCHI TAX H5186 STA HA600,X ;zero out 1024 bytes INX CPX #$80 BNE H5186 RTS PRSCRN PHA ;save accumulator LDA #$12 ;save as horizontal position STA $24 PLA ;restore acc JSR PRINT ;print character in acc at horiz RTS SETUP LDA H9E00 CMP #$4C BEQ H51CC LDA #$4C STA H9E00 LDA #$00 STA H9E01 LDA #$4F STA H9E02 LDA $04 PHA LDA $05 PHA LDA #$2C STA $04 LDA #$52 STA $05 JSR GETBYT PLA STA $05 PLA STA $04 LDA #$00 ;flag it as no bad send STA BADSEND RTS H51CC LDA #$00 STA H9E00 STA H9E02 LDA $04 PHA LDA $05 PHA LDA #>H522C STA $04 LDA #

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