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Thingamajig
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Make the emulator run at roughly 500 KIPS and bodge the line feed to work properly on Linux

This commit is contained in:
CrazyEttin 2022-08-23 18:37:59 +03:00
parent be38167923
commit 582c13630c
2 changed files with 36 additions and 7 deletions
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29
emulator.pas
View File

@ -30,6 +30,7 @@ var
State: file of Tape; //File storing the states of the tape reader and punch
{$endif}
Ch, Scan: ansichar; //Character for input and output and scancode for non-ASCII keys
IC, LFX: integer; //Instruction counter for CPU speed
//Terminal output
procedure Output;
@ -38,7 +39,11 @@ begin
if Ch <= ansichar ($1f) then begin
if Ch = ansichar (7) then write (Ch) //Bell
else if Ch = ansichar (8) then write (Ch) //Backspace
else if Ch = ansichar ($a) then write (Ch) //Line feed
else if Ch = ansichar ($a) then begin //Bodge for line feed
LFX := WhereX;
write (Ch);
GotoXY (LFX, WhereY);
end
else if Ch = ansichar ($d) then write (Ch) //Carriage return
else write (''); //Others
end
@ -47,12 +52,21 @@ begin
else write (Ch);
end;
//Wait to emulate CPU speed of ~500 KIPS
procedure wait;
begin
if IC div 500 = 0 then sleep (1)
else sleep (IC div 500);
IC := 0;
end;
begin
//Initialise the halt flag and the pointers
//Initialise the halt flag, the pointers, and the instruction counter
Hlt := false;
IP := 0;
RP := $fff0;
IC := 0;
//Initialise the tape reader and punch
{$ifdef tape}
@ -163,6 +177,7 @@ begin
else if Op = $a then begin
//Terminal input
if Addr = IO then begin
wait;
//Read a keypress
repeat
Ch := ReadKey;
@ -209,6 +224,7 @@ begin
//Tape reader
{$ifdef tape}
else if Addr = $fffd then begin
wait;
assign (State, ExpandFileName ('~/.tapes.thingamajig'));
//Check the reader state
if FileExists (ExpandFileName ('~/.tapes.thingamajig')) then begin
@ -250,12 +266,14 @@ begin
else if Op = $b then begin
//Terminal output
if Addr = IO then begin
wait;
Ch := ansichar (R [X]);
Output;
end
//Printer
{$ifdef printer}
else if Addr = $fffe then begin
wait;
assign (Prn, '/dev/usb/lp0');
try
rewrite (Prn);
@ -268,6 +286,7 @@ begin
//Tape punch
{$ifdef tape}
else if Addr = $fffd then begin
wait;
assign (State, ExpandFileName ('~/.tapes.thingamajig'));
//Check the punch state
if FileExists (ExpandFileName ('~/.tapes.thingamajig')) then begin
@ -322,7 +341,6 @@ begin
end;
end
{$endif}
//Regular store
else Mem [Addr] := R [X];
end
@ -385,6 +403,11 @@ begin
end;
end;
//Increment the instruction counter
IC := IC + 1;
end;
wait;
end.

14
readme.md
View File

@ -8,12 +8,18 @@ https://ahti.space/git/crazyettin/Thingamajig.
Included Software
-----------------
The repository includes an emulator implementation of Thingamajig, a
The repository includes an emulator implementation of Thingamajig with a
control program for the emulated punched tape reader and punch, and an
assembler and a disassembler, all written in FreePascal. It also
includes couple of simple example programs for Thingamajig written in
Assembly.
Speed
-----
Thingamajig does not have a prescribed speed. The emulator should run at
roughly 500 KIPS.
Registers and Memory
--------------------
@ -86,8 +92,8 @@ reference to or relative to a label.
Memory-Mapped Devices
---------------------
Input (when read from) and output (when written to) are mapped to
address FFFF. The emulator emulates a glass teletype with local echo.
Input and output are mapped to address FFFF. The emulator emulates a
glass teletype with local echo.
Arbitrary devices can be mapped to the other reserved addresses.
@ -102,7 +108,7 @@ to modify the code yourself.
Initial Program Loader
----------------------
At boot the initial program loader loads a program to the memory
At boot the initial program loader (IPL) loads a program to the memory
starting from address 0 after which is cedes control to the CPU. The
emulator loads the program from a ROM file.