PlotBASIC commands can be found on pg 9 of the TOSIE newsletter July/83 issue.
Edit: Ooops, I don't see it online. I have it, but I thought I had already scanned it. I guess I'll have to add that to my list
PLOTn(parameters) where 'n' is 0 to 8.
PLOT0(x,y) - set origin
PLOT1(x,y,chr,col) - plot a square
PLOT2 hmm, not documented
PLOT3(x,y,x2,y2,chr,col) - create rectangle
PLOT4(chr,col) - fill the screen
PLOT5(x,y) - plot a point
PLOT6(x,y,x2,y2) - plot a line
PLOT7(A$;B%(0,0);x,y) - bring in a figure from directory and position it
PLOT8(B%(0,0),dir) - move the figure in a direction (0-9)
Steve