High-performance 4-bit LCD driver written in Spin. Uses LCD busy flag to minimize delays between character writes for best performance. Driver includes code to write characters, formatted strings, to read from LCD memory, and to define custom characters.

Version 1.1 allows the specification of LCD size (cols, rows) for error trapping. Adds display(), cursor(), moveto(), and scrollstr() methods.

Version 1.2 adds initx() method to allow for non-contiguous pin group of control pins (BL, E, RW, RS). Also adds rscrollstr() for left-to-right scrolling of a string.

Version 1.3 fixes a small setup error in initx(), removes some small inefficiencies, self-adjusts or clock frequency, and adds rjdec() method for printing right-justified decimal numbers.

Version 1.4 fixes a bug that prevented LCDs using the startx method (was initx) from working properly (thanks to Eldon Brown for pointing out the problem with non-contiguous pin assignments). The init method has been renamed start() to conform with other Propeller objects, and is more efficient (calls startx).