CIGAL Reference Manual, Chapter 4 (Variables): tablet
usage: tablet = value
TABLET, an internally defined integer variable, controls how you can use a digitizing tablet to move the cursor. The value of the TABLET parameter can be changed at any time and remains set until it is explicitly modified again.
Note: In order to actually use the tablet to control the cursor you must set two other flags in addition to TABLET. You must set the appropriate flag in the CURSOR control variable (see CURSOR(4)), and also set the properties of the I/O port by assigning an appropriate value to the line control variable COM1 or COM2 (see COM1(4) or COM2(4)).
The TABLET variable has several bit-fields with different meanings. The 2 lowest bits specify to which communication port the digitizing tablet is attached. The next 10 bits indicate what format your tablet uses to send its positional data. This can be either ASCII or binary coded. If it's ASCII, then the YKKNNNNN fields (see below) should be used to specify the format. If it's binary then CIGAL will only accept data if the tablet format is one of those in the list recognized by the TT field. You set TABLET by adding the various bit fields.
Details of the bit-fields in the 16-bit TABLET variable are as follows:
mfssttykknnnnncc Tablet Parameters Communication port # ASCII Chars Select: Field: Bits: Value: Meaning: Communications CC 0-1 0 COM1 - 1st asynchronous, serial port port 1 COM2 - 2nd asynchronous, serial port 2-3 Undefined Num. of chars nnnnn 2-6 0-31 Number of ASCII characters, excluding of ASCII data CR or LF (i.e. ASCII values >= 32) Key value flag kk 7-8 0 No Key code; X and Y only 1 Key first; then X and Y 2 X and Y first; then Key 3 undefined XY order y 9 0 X value first; then Y 1 Y value first; then X Tablet type tt 10-11 1 Summagraphics BitPad (binary format) 2-3 undefined Shift factor ss 12-13 0-3 Shift X/Y values SS bits to right (i.e., divide by 2 ** ss) Y flip f 14 1 Flip Y coord. (y = ymax - y) Minus flag m 15 1 Negative values accepted (ASCII only)