• 1.774 MHz CPU clock, precise Z80 cycles times, entire Z80 command code including the non defined ones and XF/YF flags.
• Z80 Reset (F11), NMI (F12), INT lines
• All three HT-1080Z series ROMs and character generators included with selectable 16/48K memory
• Full HT keyboard with CUT (F5) and PAGE (F6) keys, Pause mode
• Tape recorder, printer, four 5 1/4" SS SD floppy disk, internal clock
• Yamaha YM2149 sound chip (originally suppurted only in HT series
• Micolor 01 (hungarian expansion board) and Lowe Electronics LE18 graphic board
• Built-in debugger
• Audio: 8 bits, Mono, 22050Hz
• Screen snapshot F8 into BMP or JPEG file
• Turbo mode, 2x or Full (20x)
• Program autostart, text file input as keyboard
• Predefined and custom "skins
• Favorites

Starting the first time

When starting the emulator the first time, it will run according to the default settings:

• No tape inserted, disk drives are empty
• HT-1080Z first series with 48K RAM
• Micolor 01 emulation enabled
• "High contrast" skin

The tape recorder

The tape recorder emulation works in real-time mode. This means, that independent of the file format, but there are some conditions: the tape writing always starts with 255 pieces 00h character. This way when reading it’s easier to find the beginning of the file, as well as the sign pitch. Actually there is also another reason for this; because of the write/read mode it must read at least 8 pcs of 0 bits continuously, before the data. The file on the start does not need to contain 255 pcs 00h character, 2 pcs are enough but it can also be more.

The file extension can be ASM, BAS or CAS. This way not every file includes the data, so the emulator supports some frequent file formats:

• .ASM - The file starts with a D3h character. The emulator will replace the missing synchronization signals and the file beginning indicating A5h character.
• .BAS - The file starts with an FFh character. The emulator will replace the missing synchronization signals and the file beginning indicating A5h character, as well as the basic type 3 pcs D3h character. It will skip the first FFh character.

Inserting/removing a tape

Click with the left button to cassette picture or select the File -> Cassette -> Insert menu item for insert.
Remove: right button on cassette or File -> Cassette -> Remove item.
Rewinding the tape: click to the REW (left key on the tape)
Only the ASM, BAS and CAS file types will be supported.

Autostart

With auto start, machine code and basic programs can load faster. This function can load CAS, CMD and BAS file formats.

Inserting/removing a disk

Same as the tape insert, only now choose any of the DISK picture (0-3 up to down) or select the File -> Disk menu.

The system can only boot from DISK 0, here we place the system disk. If the DISK 0 is empty the emulator will turn off disk emulation and the system will start in Basic after reset.

The emulator supports the most common DSK formats up to 80 Track.

Screen snapshot with inserted tape and disc

Text file input as keyboard

With File -> Text input menu item can you enter a text file as keyboard input.

Printing

The emulator includes a built-in virtual printer. To open select Printer -> Output menu.

Graphic expansion boards

Supported graphic extension boards:

Other functions

Options -> Layout menu: select the Hungarian or English layout.
Options -> Monitor menu to adjust color, contrast, brightness and scan lines emulation.
Selectable more predefined skins: Solid, Amber, Green monitors, B/W TV.

 
 

Screen snapshot

Press F8 to save sreen into BMP or JPEG file.

The built-in Debugger

The emulator includes a built-in debugger, which can be reached through the F1 key or from CPU menu.

Debugger windows:

• Assembler list
• Memory dump
• Registers
• Flag register
• Stack content
• Breakpoint list
• FDC registers

Assembler list

When stepping into the debugger the assembler list cursor will step into the actual PC value. Sometimes the cursor is not visible, since the programmer used such kind of tricks that one command operates another and this way the program will jump there. The debugger can also search backwards and displays the commands exactly.

F7 Trace Into - execute a command
F8 Step Over - execute a command, the CALL and RST commands will be called
F4 Go To Cursor - run the program till it reaches the cursor position
F9 Run - run the program with debugger screen
F6 Toggle Breakpoint - turn on/of the breakpoint of the cursor position
ESC Exit from debugger (continue program).

Memory dump

The memory will display 256 bytes in hexadecimal and ASCII format and also serves for editing the writable memory zone. Move the cursor with the up/down keys, move the pages with the PgUp/PgDn keys. Change the cursor address with the Enter key.

Registers

The CPU registers can be changed, except the PC, which can be changed only from the assembler list with the F10 key. The green color of the register values shows that they have changed since the last stop, or have been changed manually.

Flags

The flags can be changed. If the flag value is 1 its name will be displayed in red, this way you can keep track of it more easily. The flag value is green, if it has changed since the last stop, or has been changed.

Stack content

Shows the stack content, can not be changed. In case a change is necessary, this can be done via the memory dump.

Breakpoint list

Shows the breakpoint address. Go to address with left button, delete with right button.

Key summary

• F1 Debugger
• F2 Sound on/off
• F3 Color, contrast, brightness adjust, same as click to screen.
• F4 Toggle between system and Micolor screen
• F5 CUT
• F6 PAGE
• F8 Sreen snapshot
• F11 RESET
• F12 NMI
• Pause Pause / Continue

Key allocation (English)

           1 2 3 4 5 6 7 8 9 0 : - Left key
Break Q W E R T Y U I O P @
           A S D F G H J K L ;
             Z X C V B N M , . /         Up/Down/Left/Right

Home - Clear
End - Break
Enter - New Line

Program Property

1. The program is the property of Zoltán Kollár.
2. The program can be used, copied and distributed by everyone.
3. The program is free, this way no fee may be asked for it by anyone.
4. The program can solely be altered by the author.

Special thanks to István Majzik (original photos and many tests), Attila Grósz and Csaba Márkus.

Comments or ideas can be sent to zka@freemail.hu