Virtual H19 Terminal

The virtual H19 terminal implements many of the terminal features. The following keys from a modern computer keyboard are mapped to the H19 Keys as follows:

PC Key	H19 Key	Notes
F1-F5	f1-f5
F6	BLUE
F7	RED
F8	WHITE (GRAY)
Shift F9	SHIFT RESET
Scroll Lock	SCROLL	Shift applied as for H19
Shift Backspace	DELETE
Home	HOME
<Cursor>	<CURSOR>	Irrespective of which keypad
Delete	DC
Shift Delete	DL
Insert	IC	Sends ESC @ or ESC O, whichever is opposite current mode
Shift Insert	IL
Enter	RETURN	Also ENTER on keypad
Ctrl Enter	LINE FEED

All other "standard" keys should have the expected results, given a direct translation to H19 keys.

Note that the H19 keypad is emulated only when "Num Lock" is on. The terminal settings for "Alternate Keypad mode" and "Keypad Shifted", along with the "Shift" key on your keyboard, should work as expected. A modern keyboard has more keys on the keypad than the H19, and those keys do not produce values. Otherwise, the keys work as their H19 counterparts.

PC Key	H19 Key
0 / Ins	0
1 / End	1 / IL
2 / ↓	2 / ↓
3 / PgDn	3 / DL
4 / ←	4 / ←
5	5 / HOME
6 / →	6 / →
7 / Home	7 / IC
8 / ↑	8 / ↑
9 / PgUp	9 / DC
. / Del	.
Enter	ENTER

Beware that the modern keypad alternate functions do not align with the H19 keypad functions. However, the dedicated cursor/editing keys of a modern keyboard do produce the appropriate codes. For example, the "Insert" editing key produces the same codes as the Shifted "7 / IC" keypad key on the H19, but the "0 / Ins" does not produce the "IC" code when "Ins" is selected.

While most standard features are implemented, the following terminal features are NOT implemented:

• Modify Baud Rate (ESC r X)
• Keyboard Disable (ESC })
• Key Click (ESC y 2)

Note that the above codes are accepted (will not cause stray characters on the screen), but do not perform the prescribed function.

Because of the way screen characters are displayed, it is not possible to represent the cursor exactly as the H19 - in the sense that the cursor does not "invert" the character beneath it. This can lead to a cursor that is difficult to see, if not invisible, when over reverse-video characters. As a workaround, the cursor color may be set to something different from the normal video color, thus making it always discernible. The chosen color can be made close to normal video, to maintain more authenticity.

Basic copy-paste is supported. Clicking (button 1) and dragging will show a faint blue area around selected text. The area will remain highlighted for about 2 seconds after releasing the mouse button, but text is copied to the clipboard immediately. Text from the clipboard may be pasted into the Z19 "keyboard" stream using the middle mouse button. Note, however, that pasting large amounts of text may overrun the program as the data can arrive faster than human typing speed. See properties h19_paste_rate and h19_paste_cr_wait.

The following properties control the basic and initial functioning of the virtual terminal:

h19_font

The name of the (TrueType) font file to use for the H19 CRT screen. Default is "h19a.ttf" which is built-in to the JAR. This font closely resembles the original character generator (and video characteristics) of the H19. Font may be a TTF file included in the JAR, or an absolute pathname to a TTF file on your system, or the name of an installed (ISO character set) font on your system, or a JAVA generic font name (e.g. "Monospaced"). Note that only monospaced fonts are likely to work well.

For custom TTF fonts:

• The graphics characters 0x00-0x1f (in ROM locations) must be located at TTF font characters 0x100-0x11f.
• TTF font characters 0x80-0xff must represent the reverse-video version of ROM characters 0x00-0x7f.

Fonts built in to your system:

• Must support the ISO character set that includes the line drawing characters, in the '\u2500' range (in order to support H19 graphics).
• The characters for the triangle graphics symbols are not exactly the same as the H19, so some screens (such as INVADERS) will look a little different.
• Most modern fonts do not replicate the aspect ratio of the H19, so the screen dimensions will be different.
• The performance of the virtual H19 may be adversely affected by running ISO fonts.

h19_font_size

This selects the size of the font used for the H19 CRT screen. Most systems require this number to be a multiple of 10 in order to display clean characters. Default is 20, which is probably the most useful value.

h19_font_color

Selects the color to use for the H19 CRT screen. This color must have a good contrast ratio to the dark background of the screen. Format is 6 hexadecimal digits where each pair (octet) represents, respectively from hi to low, red, green, and blue. Default is "00ff00" which is the green. An amber color is "ffc000" and white would be "ffffff".

h19_cursor_color

Selects the color to use for the H19 cursor. This can be used to avoid a "disappearing cursor" when over reverse-video characters.

h19_beep

Selects the WAV file to use for the H19 "beep" sound. The default is the built-in "h19beep.wav" which is the 1/2-second, 1024Hz, beep. Other built-in files allow for different durations, "h19beep250.wav" and "h19beep125.wav", for 1/4 and 1/8 second respectively. Sound file must exist in the JAR file.

h19_beep_volume

The volume to set when sounding the H19 "beep". Values are percent of maximum volume.

h19_s401, h19_s402

Dipswitch settings for the H19. See H19/Z19 owner's manual. Settings related to serial port (s401) have no affect, but many terminal features defaults (s402) are supported. Values are 8-bit binary, with the left-most digit being the MSB, corresponding to switch 7. A "0" represents an OFF switch.

h19_paste_rate, h19_paste_cr_wait

These are used to control the rate at which text is pasted to the computer console. "h19_paste_rate" is the rate for normal characters, in characters per second (values 1 to 1000). The default is 30. "h19_paste_cr_wait" is the delay in milliseconds used after RETURN, in place of h19_paste_rate. Default is 100 mS. These values are used to prevent overrun of the computer software for pasted text.