 2Т IBM disc dump utility program by Mark Holmes 
Т Main program loop К7 ч buffer &1500 (buffer=(buffer+&FF) ─ &FF00 2
Рsetup <У F2  Рprompt("Press D(ir), F(iledump) or Q(uit)") P  K%=╔ ─ &DF Z"  Г K%=≈"D":Рdisplay_directory n  Г K%=≈"F":Рfile_dump xЩ K%=≈"Q" ┌К7 ▄Ю х"Т Print out IBM disc directory рщРdisplay_directory эш Ф)cluster=єget_dir("display directory") ПА,%Т Dump contents of file to screen6щРfile_dump@О 28,3,24,39,24,12J!Х ┼4);"Enter Filename: "name$TО 28,0,23,39,2^Рprompt(name$)hшr*cluster=єget_dir(єname_convert(name$))|XГ cluster=-1:Я ┼10,5);name$;" not found":Рprompt("Press any key to continue"):K%=╔:А├YГ cluster=0:Я ┼10,5);name$;" has no data":Рprompt("Press any key to continue"):K%=╔:А░block_address%=0 Ує  Рconvert(cluster)ў$  cluster=єnext_cluster(cluster)╦'  Рdump(buffer,&200,block_address%)б(  block_address%=block_address%+&200лЩ cluster>&FEFжАТ#Т Loop until WD1770 is not busyЧ
щРwait$У:Щ((?status_reg) ─ busy_bit)<>1АXТ read sector from discb,щРread_sector(side,track,sector,address)l@Г address<>0:?(save+1)=address ┐ 256:?(save+2)=address │ 256v6Г side=1:value=(value └ &10) ▀ value=(value ─ &EF)─?dr_ctrl_reg=value┼?data_reg=track■?comm_reg=&19·	Рwait╗?track_reg=track │ double╡?sector_reg=sector╪?comm_reg=&84ф	РwaitпQГ ((?status_reg) ─ error_bit)=&10:Я"DATA ERROR: ";side;" ";track;" ";sector:Юз?track_reg=trackДА ,Т Initialise disc drive control register*#щРdisc_init(drive,side,density)4value=4>+Г drive=1:value=value+2 ▀ value=value+1HГ side=1:value=value+&10R Г density<>2:value=value+&20\?dr_ctrl_reg=valuef?comm_reg=&09p	РwaitzА└&Т Search for filename in directory▌щєget_dir(search$)≤I=dir_buffer╒У╛  Г ?I<>&E5:B=єshow_nameІ  I=I+32ю,Щ (I=dir_buffer+112*32) └ (?I=0) └ B<>-1й=BХ-Т Compare search name to directory entry,И?Т Return cluster number or -1 if no file or 0 if empty fileРщєshow_nameЭfname$=""Ц J=0 ╦ 10  fname$=fname$+Ґ(I?J)М$fat=(I!26) ─ &FFFF.BГ search$="display directory":Яюfname$,8);".";бfname$,3);"  ";8Г ╠=2:О 13BГ fname$=search$:=fat ▀ =-1п4Т Return next cluster from file allocation tableзщєnext_cluster(start)Д(fat_entry=fat_buffer!((start │ 2)*3)Нbyte1=fat_entry ─ &FFЬ"byte2=(fat_entry ─ &FF00)/&100&byte3=(fat_entry ─ &FF0000)/&10000,Г start ┐ 2=0:=byte1+((byte2 ─ &F)*&100)(Г start ┐ 2=1:=byte2/&10+(byte3*&10)╦6Т convert cluster number to physical disc locationбщРconvert(cluster_no)л#log_sector =(cluster_no-2)*2+12ж$phys_side  =(log_sector │ 9) ┐ 2Ю&log_track  =(log_sector │ (9 * 2))Й$phys_sector=(log_sector ┐ 9) + 1Т8Рread_sector(phys_side,log_track,phys_sector,buffer)ЧА═Т dump data to screen╙)щРdump(where%,how_much%,file_offset%)Є(Ц I%=where% ╦ where%+how_much%-8 ┬ 8Ў
  @%=6х.  Я Ґ(129);~file_offset%+I%-where%,Ґ(135);р
  @%=1э  Ц J%=0 ╦ 7Ф-    Я ~(I%?J% ─ &F0)/&10,~I%?J% ─ &F," ";П  МЗ  Я Ґ(8);Ґ(131);  Ц J%=0 ╦ 75    Г (I%?J%>31) ─ (I%?J%<127):ЯҐ(I%?J%); ▀ Я".";  М"  Я,М6А┬3Т Set up variables, load directory and fat etc.▓щРsetup⌠%A%=0:X%=1:A%=((╨&FFF4)─&FF00)│256■)machine$="MASTER":ГA%=2:machine$="B+"°0Г A%>2:dr_ctrl_reg=&FE24 ▀ dr_ctrl_reg=&FE80і0Г A%>2:WD1770_addr=&FE28 ▀ WD1770_addr=&FE84╟comm_reg=WD1770_addr╨status_reg=WD1770_addrдtrack_reg=WD1770_addr+1нsector_reg=WD1770_addr+2ьdata_reg=WD1770_addr+3Бbusy_bit=&01Лerror_bit=&10ЖЦ opt%=0 ╦ 2 ┬ 2  P%=&D00        :Т NMI adress[OPT opt%(4      PHA            \ save accumulator on stack24      LDA status_reg \ get status register value</      ─ #&1F       \ mask out unwanted bitsF1      CMP #&03       \ data ready & busy bitsP0      BNE exit       \ not interested in NMIZ6      LDA data_reg   \ get data from data registerd%.save STA &2000      \ store datan4      INC save+1     \ increment sabe adress LSBx4      BNE &0D18      \ not page boundary so exit┌4      INC save+2     \ increment save adress MSB╦..exit PLA            \ restore accumulator√0      RTI            \ return from interruptх]:М opt%ФО23,1;0;0;0;0П"Я Ґ(135);Ґ(157);Ґ(132);Ґ(141);!Я ┼8);"IBM disc dump utility"""Я Ґ(135);Ґ(157);Ґ(132);Ґ(141);,!Я ┼8);"IBM disc dump utility"6"Я ┼0,24);Ґ(135);Ґ(157);Ґ(132);@"Я ┼0,23);Ґ(135);Ґ(157);Ґ(132);J(Рprompt("Press any key to continue")TО28,0,23,39,2,12^,Я ┼5,5);"Put IBM format disc in drive 0"hK%=╔rш|fat_buffer=buffer+&200├dir_buffer=buffer+&200+&400░%drive=0:density=2:side=0:double=1 "Рdisc_init(drive,side,density)⌡"Рread_sector(0,0,1,fat_buffer)°)dir=1 + fat_buffer?16 * fat_buffer?22² Г fat_buffer?21>&F9:double=2є"Рread_sector(0,0,2,fat_buffer)ўРread_sector(0,0,3,0)╦Рread_sector(0,0,4,0)бРread_sector(0,0,5,0)л:Рread_sector((dir+0) │ 9,0,((dir+0) ┐ 9)+1,dir_buffer)ж1Рread_sector((dir+1) │ 9,0,((dir+1) ┐ 9)+1,0)Ю1Рread_sector((dir+2) │ 9,0,((dir+2) ┐ 9)+1,0)Й1Рread_sector((dir+3) │ 9,0,((dir+3) ┐ 9)+1,0)Т1Рread_sector((dir+4) │ 9,0,((dir+4) ┐ 9)+1,0)Ч1Рread_sector((dir+5) │ 9,0,((dir+5) ┐ 9)+1,0)1Рread_sector((dir+6) │ 9,0,((dir+6) ┐ 9)+1,0)Аp'Т Place message at bottom of screenzщРprompt(message$)└О 28,3,24,39,24,12▌&Я ┼(34-╘(message$))/2,0);message$;≤О 28,0,23,39,2╒АX,Т Convert filename into directory formatbщєname_convert(string_in$)lI%=їstring_in$+".",".")v0string_out$=ююstring_in$,I%-1)+д9-I%," "),8)─6string_out$=string_out$+юаstring_in$,I%+1)+"  ",3)┼=string_out$■	Е█tT[Ъ