Two modes:
 'C' mode for printing upper case only characters
 'P' mode for plot mode

In 'C' mode the following escape characters are recognised:
 1 - switch to 'C' mode
 2 - switch to 'B' mode
 3 - magnify characters 2x
 4 - magnify characters 4x
 5 - magnify characters 8x
 6 - magnify characters 1x
 8 - backspace
10 - line feed
13 - carrage return + line feed
17 - rotate 0°
18 - rotate 90°
19 - rotate 180°
20 - rotate 270°
32-122 - standard ASCII chars (all upper case)

In 'P' mode the following commands are recognised:
G00 - straight dotted line segment
      G00 [X|U]nn [Y|V]nn
G01 - straight solid line segment
      G01 [X|U]nn [Y|V]nn
G02 - solid clockwise arc segment
      G02 [X|U]nn [Y|V]nn Imm Jmm
G03 - solid counter-clockwise arc segment
      G03 [X|U]nn [Y|V]nn Imm Jmm
G50 - pen up movement
      G50 [X|U]nn [Y|V]nn
G90 - solid rectangular figure
      G90 [X|U]nn [Y|V]nn
G91 - solid triangular figure
      G91 [X|U]nn [Y|V]nn

Arguments to commands:
Xnn - x-coordinate end point
Ynn - y-coordinate end point
Imm - x-coordinate arc center
Jmm - y-coordinate arc center
Unn - x-coordinate ?
Vnn - y-coordinate ?

nn and mm may be positive or negative ('-' sign)
the range of U and V is -32767 to 32767.
the range of X, Y, I and J is -16383 to 16383.

The width of the paper is 0 to 1964.