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Add disc formatting and deal with disc sectors with an unset sync bit

This commit is contained in:
CrazyEttin 2022-09-23 13:25:08 +03:00
parent bf36aab7a4
commit 23b32d7835
2 changed files with 96 additions and 19 deletions
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96
emulator.pas
View File

@ -289,15 +289,15 @@ begin
if B <= $4c then begin
if DiscDrive = 0 then begin
{$ifndef fast}
if Disc0Track > B then wait (((Disc0Track - B) * 10) + 45 )
else if B > Disc0Track then wait (((B - Disc0Track) * 10) + 45 );
if Disc0Track > B then wait (((Disc0Track - B) * 10) + 45)
else if B > Disc0Track then wait (((B - Disc0Track) * 10) + 45);
{$endif}
Disc0Track := B;
end
else begin
{$ifndef fast}
if Disc1Track > B then wait (((Disc1Track - B) * 10) + 45 )
else if B > Disc1Track then wait (((B - Disc1Track) * 10) + 45 );
if Disc1Track > B then wait (((Disc1Track - B) * 10) + 45)
else if B > Disc1Track then wait (((B - Disc1Track) * 10) + 45);
{$endif}
Disc1Track := B;
end;
@ -316,7 +316,11 @@ begin
else if W = $fffb then begin
B := B and $f;
//Reset the system
if B and $c = 0 then begin
if B and $e = 0 then begin
{$ifndef fast}
if ((Disc0Track * 10) + 45 ) > ((Disc1Track * 10) + 45 ) then wait ((Disc0Track * 10) + 45)
else wait ((Disc1Track * 10) + 45);
{$endif}
Disc0Track := 0;
Disc1Track := 0;
Disc0Sect := 0;
@ -328,6 +332,72 @@ begin
for DiscSBP := 0 to $88 do DiscSB [DiscSBP] := 0;
DiscSBP := 0;
end
//Format the disc
else if B and $e = 2 then begin
if DiscRead = false then if DiscWrite = false then if DiscTrackSet = false then if DiscSectSet = false then begin
{$ifndef fast}
wait (30000);
{$endif}
assign (Discs, ExpandFileName ('~/.thingamajig/discs'));
//Check the system state
if FileExists (ExpandFileName ('~/.thingamajig/discs')) then begin
try
reset (Discs);
read (Discs, Disc0Path);
read (Discs, Disc1Path);
close (Discs);
except
end;
end;
//Set the drive
if B and 1 = 0 then DiscPath := Disc0Path
else DiscPath := Disc1Path;
if DiscPath <> '' then begin
assign (Disc, DiscPath);
//Write
try
reset (Disc);
if FileSize (Disc) = $526a0 then begin
if B and 1 = 0 then begin
for Disc0Track := 0 to $4c do begin
for Disc0Sect := 0 to $1f do begin
for DiscSBP := 0 to $88 do begin
seek (Disc, (Disc0Track * $1120) + (Disc0Sect * $89) + DiscSBP);
if DiscSBP = 0 then write (Disc, $80)
else write (Disc, 0);
end;
end;
end;
end
else begin
for Disc1Track := 0 to $4c do begin
for Disc1Sect := 0 to $1f do begin
for DiscSBP := 0 to $88 do begin
seek (Disc, (Disc1Track * $1120) + (Disc1Sect * $89) + DiscSBP);
if DiscSBP = 0 then write (Disc, $80)
else write (Disc, 0);
end;
end;
end;
end;
close (Disc);
Disc0Track := 0;
Disc1Track := 0;
Disc0Sect := 0;
Disc1Sect := 0;
DiscRead := false;
DiscWrite := false;
DiscTrackSet := false;
DiscSectSet := false;
for DiscSBP := 0 to $88 do DiscSB [DiscSBP] := 0;
DiscSBP := 0;
end
else close (Disc);
except
end;
end;
end;
end
//Read a sector from the buffer to the computer
else if B and $e = 4 then begin
if DiscWrite = false then if DiscTrackSet = false then if DiscSectSet = false then begin
@ -382,11 +452,17 @@ begin
try
reset (Disc);
if FileSize (Disc) = $526a0 then begin
for DiscSBP := 0 to $88 do begin
if B and 1 = 0 then seek (Disc, (Disc0Track * $1120) + (Disc0Sect * $89) + DiscSBP)
else seek (Disc, (Disc1Track * $1120) + (Disc1Sect * $89) + DiscSBP);
read (Disc, DiscSB [DiscSBP]);
end;
if B and 1 = 0 then seek (Disc, (Disc0Track * $1120) + (Disc0Sect * $89))
else seek (Disc, (Disc1Track * $1120) + (Disc1Sect * $89));
read (Disc, DiscSB [0]);
if DiscSB [0] and $80 = $80 then begin
for DiscSBP := 1 to $88 do begin
if B and 1 = 0 then seek (Disc, (Disc0Track * $1120) + (Disc0Sect * $89) + DiscSBP)
else seek (Disc, (Disc1Track * $1120) + (Disc1Sect * $89) + DiscSBP);
read (Disc, DiscSB [DiscSBP]);
end;
end
else for DiscSBP := 0 to $88 do DiscSB [DiscSBP] := 0;
close (Disc)
end
else begin

19
readme.md
View File

@ -125,28 +125,29 @@ punch to FFFD, and the disc system to FFFB and FFFC. The printer prints
into /dev/usb/lp0. The tape files read from and punched to are (re)set
using the program tapectl with the arguments -r and -p respectively and
the disc files in drives 0 and 1 using the program floppyctl with the
arguments -0 and -1 respectively. The disc system uses single-sided
discs with 77 tracks of 32 sectors of 137 bytes, or 337568 bytes in
total: the disc files must be of this size.
arguments -0 and -1 respectively. The disc system uses hard sectored
single-sided discs with 77 tracks of 32 sectors of 137 bytes, or 337568
bytes in total: the disc files must be of this size.
The floppy disc system uses two ports: command at FFFB and data at FFFC.
Only the low nibble of the command port is used, consisting of a
three-bit command followed by a one-bit drive number used as an argument
by instructions 4-7. The track or sector to be accessed is input to and
the buffer accessed sequentially through the data port after the
by instructions 1 and 4-7. The track or sector to be accessed is input
to and the buffer accessed sequentially through the data port after the
relevant command is input to the command port. New commands other than
resetting the system are ignored until the current command is fully
executed.
executed. Note that each sector begins with a synchronisation bit that
must always be set.
The commands for the disc system are:
0: Reset the system.
1: "
1: Format a disc.
2: Read a sector from the buffer to the computer.
3: Write a sector from the computer to the buffer.
4: Set the track to be accessed.
5: Set the sector to be accessed.
6: Read a sector from the disc to the buffer.
7: Write a sector from the buffer to the disc.
6: Read a sector from a disc to the buffer.
7: Write a sector from the buffer to a disc.
The IPL loads the program specified as an argument when running the
emulator.