US. Patent
May 19, 1993
Sheet 7 of 9
901
READ SCANNER
CHIP SENSOR “902
MEMORY
l
COMPARE NEW
AND OLD
N903
READINGS
l
rmo INPUT
THAT CAUSED N904
INTERRUPT
l
CONVERT tNPUT
POSITION T0
\905
A cool;
i
PUT c005 INTO N906
INPUT QUEUE
R513?
INTERRUPT
FIG 9
5,754,960
