Apparatus for high speed image rotation

DETAILED DESCRIPTION It is a principal object of the present invention to provide an improved high speed character generator.
It is another principal object of the present invention to provide novel logic circuitry for rotating a character stored in a character memory in the form of a bit matrix.
It is another principal object of the present invention to provide logic circuitry for rotating a single bit matrix character stored in memory by 90.
degree.
.
It is another object of the present invention to provide logic loop circuitry for rotating a bit matrix character by 90.
degree.
.
It is another object of the present invention to provide a logic circuit loop comprising a barrel shifter and a linear array shifter for rotating characters stored in a memory by 90.
degree.
.
According to these and other objects of the present invention, there is provided means for reading micro column word slices of a bit matrix character out of memory one word slice at a time into a barrel shifter.
The first pass output of the barrel shifter is routed through a linear array shifter and fed back to the input of the barrel shifter.
The second pass output of the barrel shifter rotates the word slices to provide a bit matrix character which is rotated 90.
degree.
from the first pass bit matrix character read from memory