amiga-bootcamp/10_devices/console.md

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console.device — Text Terminal I/O

Overview

console.device provides an ANSI-compatible text terminal within Intuition windows. It handles:

• Input: translating raw keycodes from input.device into ASCII/ANSI characters
• Output: rendering text, parsing escape sequences for cursor control, color, and formatting
• Clipboard: cut/copy/paste integration

Every CLI/Shell window is backed by a console.device unit. Applications can open their own console units in any Intuition window for text I/O without implementing their own keyboard translation or cursor rendering.

flowchart LR
    KB["Keyboard<br/>(raw keycodes)"] --> INPUT["input.device"]
    INPUT --> CON["console.device"]
    CON -->|"Read: ASCII chars"| APP["Application"]
    APP -->|"Write: text + ESC sequences"| CON
    CON -->|"Renders text via<br/>RastPort drawing"| WIN["Intuition Window"]

    style CON fill:#e8f4fd,stroke:#2196f3,color:#333
    style WIN fill:#c8e6c9,stroke:#2e7d32,color:#333

---

Opening

struct MsgPort *conPort = CreateMsgPort();
struct IOStdReq *con = (struct IOStdReq *)
    CreateIORequest(conPort, sizeof(struct IOStdReq));

/* Attach to an Intuition window: */
con->io_Data   = (APTR)window;
con->io_Length = sizeof(struct Window);

if (OpenDevice("console.device", CONU_STANDARD, (struct IORequest *)con, 0))
{
    /* error — can't open console */
}

Unit Types

Unit	Constant	Description
0	CONU_STANDARD	Full-feature console with cursor and scrolling
1	CONU_CHARMAP	Character-mapped console (OS 3.0+) — faster for full-screen updates
3	CONU_SNIPMAP	Snip-mapped: supports clipboard cut/paste (OS 3.0+)
-1	CONU_LIBRARY	Library mode — no window, just keymap translation

---

Writing Text and Escape Sequences

/* Write text to the console window: */
void ConPuts(struct IOStdReq *con, char *str)
{
    con->io_Command = CMD_WRITE;
    con->io_Data    = (APTR)str;
    con->io_Length  = -1;  /* -1 = null-terminated */
    DoIO((struct IORequest *)con);
}

/* Usage: */
ConPuts(con, "Hello, Amiga!\n");
ConPuts(con, "\033[1mBold text\033[0m\n");        /* bold on/off */
ConPuts(con, "\033[33mYellow text\033[0m\n");      /* color */
ConPuts(con, "\033[10;20HText at row 10 col 20");  /* absolute position */

---

Reading Input

/* Read characters (blocking): */
char buffer[256];
con->io_Command = CMD_READ;
con->io_Data    = (APTR)buffer;
con->io_Length  = sizeof(buffer);
DoIO((struct IORequest *)con);
/* con->io_Actual = number of bytes read */

/* Non-blocking read via SendIO + WaitPort: */
con->io_Command = CMD_READ;
con->io_Data    = (APTR)buffer;
con->io_Length  = 1;  /* read 1 char at a time */
SendIO((struct IORequest *)con);

/* Wait for input alongside other events: */
ULONG consoleSig = 1 << conPort->mp_SigBit;
ULONG windowSig  = 1 << window->UserPort->mp_SigBit;

ULONG sigs = Wait(consoleSig | windowSig);
if (sigs & consoleSig)
{
    WaitIO((struct IORequest *)con);
    char ch = buffer[0];
    /* process character... */
}

---

ANSI Escape Sequences

Console.device supports a rich subset of ANSI/VT100 escape sequences (CSI = \033[ = ESC + [):

Cursor Movement

Sequence	Description	Example
\033[nA	Cursor up n lines	\033[5A = up 5
\033[nB	Cursor down n lines
\033[nC	Cursor right n columns
\033[nD	Cursor left n columns
\033[y;xH	Move to row y, column x (1-based)	\033[1;1H = home
\033[H	Home cursor (top-left)
\033[6n	Report cursor position → replies \033[y;xR
\033[s	Save cursor position
\033[u	Restore cursor position

Erasing

Sequence	Description
\033[J	Clear from cursor to end of screen
\033[1J	Clear from start of screen to cursor
\033[2J	Clear entire screen
\033[K	Clear from cursor to end of line
\033[1K	Clear from start of line to cursor
\033[2K	Clear entire line

Text Attributes (SGR)

Sequence	Effect
\033[0m	Reset all attributes
\033[1m	Bold (high intensity)
\033[3m	Italic
\033[4m	Underline
\033[7m	Inverse video (swap fg/bg)
\033[22m	Normal intensity (cancel bold)
\033[23m	Cancel italic
\033[24m	Cancel underline

Colors

Sequence	Foreground	Background
\033[30m / \033[40m	Black	Black
\033[31m / \033[41m	Red	Red
\033[32m / \033[42m	Green	Green
\033[33m / \033[43m	Yellow/Brown	Yellow/Brown
\033[34m / \033[44m	Blue	Blue
\033[35m / \033[45m	Magenta	Magenta
\033[36m / \033[46m	Cyan	Cyan
\033[37m / \033[47m	White	White
\033[39m / \033[49m	Default	Default

Note

Color indices map to the Intuition pen palette of the window's screen, not absolute colors. Pen 0 = background, pen 1 = foreground by default.

Amiga-Specific Extensions

Sequence	Description
\033[>1h	Enable auto-scroll
\033[>1l	Disable auto-scroll
\033[ p	Enable cursor
\033[0 p	Disable cursor
\033[t / \033[b	Set top/bottom scroll margins
\033[20h	Linefeed mode (LF = CR+LF)

---

Raw Key Events

In addition to ASCII, console.device reports special keys as multi-byte escape sequences:

Key	Sequence Received
Cursor Up	\033[A
Cursor Down	\033[B
Cursor Right	\033[C
Cursor Left	\033[D
Shift+Up	\033[T
Shift+Down	\033[S
F1–F10	\033[0~ – \033[9~
Shift+F1–F10	\033[10~ – \033[19~
Help	\033[?~

---

Proper Shutdown

/* Must abort any pending read before closing: */
if (!CheckIO((struct IORequest *)con))
{
    AbortIO((struct IORequest *)con);
    WaitIO((struct IORequest *)con);
}
CloseDevice((struct IORequest *)con);
DeleteIORequest((struct IORequest *)con);
DeleteMsgPort(conPort);

---

CON: and RAW: Handlers

The AmigaDOS file handlers CON: and RAW: are wrappers around console.device:

Handler	Description
CON:	Line-buffered console — input is buffered until Enter is pressed. Supports line editing.
RAW:	Raw console — each keypress is delivered immediately. No line editing.

/* Open a CON: window from DOS: */
BPTR fh = Open("CON:0/0/640/200/My Window/CLOSE", MODE_OLDFILE);
FPuts(fh, "Type something: ");
char buf[80];
FGets(fh, buf, sizeof(buf));
Close(fh);

/* RAW: for unbuffered key-by-key input: */
BPTR raw = Open("RAW:0/0/640/200/Raw Input", MODE_OLDFILE);
/* Each Read returns immediately with 1 char */

---

References

• NDK39: devices/conunit.h, devices/console.h
• ADCD 2.1: console.device autodocs
• See also: keyboard.md — raw keycode to console.device pipeline
• See also: input.md — input handler chain