Amstrad DDI-1 manual Seth, Setpc

pe

(pen erase) Changes the turtle's pen colour to 0, the background colour; the turtle erases drawn lines.

?fd 50 ?pe ?bk 25 ?fd 50 ?pd fd 25

pu

(pen up) Picks the turtle's pen up; the turtle stops drawing.

?fd 30 ?pu ?fd 30 ?pd fd 30

px

(pen reverse) Makes the turtle change the colour of any previously coloured pixel in its trail to the reverse or logical colour compliment.

?fd 20 pu fd 20 ?pd setpc 3 fd 20 ?px

?bk 80 ?fd 80 ?pd bk 100

rt

Rotates the turtle the input number of degrees to the right.

?rt 90

seth

(set heading) Turns the turtle to the absolute heading specified by the input number of degrees; positive numbers turn the turtle clockwise; negative numbers turn the turtle counter-clockwise.

?seth 90

setpc

(set pen colour) Sets the turtle's pen to that specified by the input number. 0 is the background colour.

? setpc 1

AMSTRAD Disc Drive & Interface DDI-1 Manual Chapter 4.16