AVATAR Version 0.88
The Avigo Terminal Emulator
1999,2000 Curtis F Kaylor
curtis@lostmind.com


WARNING: Since previous versions of Avatar can potentially crash the Avigo, 
only versions .75 and above should be used.

Connection
Use with the cradle to communicate with a terminal program loaded on a PC.  
To use with a modem, the cradle can be used along with a male to male null 
modem cable.  The remote computer should be set to 8 bits, 1 Stop Bit, 
No Parity, Xon/Xoff Flow Control.  

The Menu Bar
The (M) button displays an informational dialog box.
Port Selection.....: Avatar defaults to the RS-232 port. To switch to the
                     IrDA port (and back) click on the text in the menubar.
                     Note: Avatar does not support the IrDA protocol, only
                     raw serial communications through the IrDA port.
BPS Rate Selection.: To change the BPS rate from the default of 9600, click 
                     on the BPS rate text in the menubar.  
                     Supported BPS rates are 1200, 2400, 4800, 9600, 19200,
                     38400, 57600, and 115200.  Other rates lower than 
                     115200 can be added upon request.
Local Echo.........: Often incorrectly called Full Duplex (no local echo)
                     and Half Duplex (local echo), I have chosen the same 
                     misnomenclature because it took up less space on the
                     menubar.  To switch "duplex" touch the half/full text
                     in the menubar.
Flow Control.......: Avatar uses software flow control (X-On/X-Off) to
                     stop incoming characters during processor intensive
                     tasks, such as scrolling the screen.  However, Avatar
                     ignores incoming flow control characters.  Hardware
                     flow control is not available, due to the fact that 
                     the Avigo uses a three wire serial connection.
Exiting the program: To exit Avatar, press the X icon in the upper right
                     corner of the menubar.  Avatar saves the communications 
                     parameters, so all the menubar selections will be the
                     same when the application is rerun. 

Using the Keyboard
Avatar sports a PC style QWERTY keyboard.  The QWERTY keyboard will 
generate all 128 standard ASCII characters.  Control characters are 
produced by tapping CTL then @, A-Z, [, \, ], or _.  The keyboard 
clicks if Stylus Tone is checked in system setup.

The function keys and cursor keys generate escape sequences:

	Key	VT52	VT100
	F1	Esc P	Esc O P
	F2	Esc Q	Esc O Q
	F3	Esc R	Esc O R
	F4	Esc S	Esc O S
	F5	Esc T	Esc O T
	F6	Esc U	Esc O U
	F7	Esc V	Esc O V
	F8	Esc W	Esc O W
	Up	Esc A	Esc O A
	Down	Esc B	Esc O B
	Right	Esc C	Esc O C
	Left	Esc D	Esc O D

Terminal Characteristics
The screen is 40 columns wide and 25 rows high.  The standard ASCII 
character set is implemented as well as the IBM high order graphics 
character set.  My own experiments have shown some problems with high 
ASCII characters.  Please let me know if you can get it to work.

The following control characters are recognized:
 7  Bell             Warning Beep (if Alarm Sound and Stylus Tone are both
                     checked in System Setup)
 8  Back Space       Moves cursor one position to the left and erases the
                     character at that position.
 9  Tab	             Advances cursor to next Tab stop.  Tab stops are eight
                     characters apart.
10  Line Feed        Moves cursor to beginning of next line.
12  Form Feed        Clears screen and homes cursor.
13  Carriage Return  Moves cursor to beginning of current line.

80 Column mode
The 80 column mode gives a virtual 80 column screen, with the physical 40 
column screen acting as a window.  To switch between 40 and 80 column mode, 
press the "40" or "80" in the menubar.  When in 80 column mode, the menubar 
will read either 80L, 80C, 80R, depending on whether the physical screen 
is showing the Left, Center, or Right view of the virtual screen.  To 
toggle between views, tap the terminal screen area (where the characters 
display).

Terminal Emulation
Avatar starts out in VT52 emulation and switches to VT100 emulation when 
an Esc < or Esc [ is encountered.  The only way to switch back to VT52 is 
to exit and reenter the application.  When using Avatar in VT100 mode, it 
should be in 80 column mode.

VT-52/VT-100 Emulation
VT-52 emulation was chosen because it is easily emulated, is fairly well 
supported and at least two other computers use VT-52 control codes: The 
TRS-80 Model 100 and Atari ST.  A subset of VT100 codes has been 
implemented.  All the codes specified in the standard Unix termcap are 
included, as well as some extras.

    Sequence  VT-52 Mode                        VT-100 Mode
    Esc A     Cursor Up
    Esc B     Cursor Down
    Esc C     Cursor Right
    Esc D     Cursor Left                       Scroll Up
    Esc E     Clear Screen
    Esc H     Cursor Home
    Esc I     Reverse Line Feed
    Esc J     Erase to End of Screen
    Esc K     Erase to End of Line
    Esc L     Line Insert 
    Esc M     Line Delete 	
    Esc Ylc   Cursor Position(Row+32,Col+32)   
    Esc [ A                                     Cursor Up
    Esc [ C                                     Cursor Down
    Esc [ C                                     Cursor Right
    Esc [ D                                     Cursor Left
    Esc [ E                                     Line Feed
    Esc [ F                                     Reverse Line Feed
    Esc [ col G		                        Position Cursor (On Line)
    Esc [ row ; col H                           Position Cursor (On Screen)
    Esc [ J                                     Erase to End of Line
    Esc [ 2 J                                   Clear Screen
    Esc [ K                                     Erase to End of Line
    Esc [ L                                     Line Insert
    Esc [ M                                     Line Delete

Except where noted, numeric parameters after the left bracket are ignored.

Future enhancements
Copy Screen to Clipboard/Memo
Landscape Mode
