TC1796
Peripheral Units (Vol. 2 of 2)
General Purpose Timer Array (GPTA)
User’s Manual
24-22
V2.0, 2007-07
GPTA, V2.0
Figure 24-14 Compensation of Input Jitter
Positioning System with Three Sensors
The 3-sensor Mode is enabled when bit PDLCTR.TSEx is set to 1. The sensors are
mounted at an 120
°
angle to each other (see
). This configuration can
measure an absolute position with a resolution of 60
°
.
Input signal combinations that are not allowed in a properly-working positioning system
(all inputs low or all inputs high) cause the following to occur:
•
An error signal is generated, driving the Duty Cycle Measurement cells DCM1 and/or
DCM3,
•
The error flag PDLCTR.ERRx is set,
•
No forward or backward pulses are generated.
When the error disappears, the error signal will be cleared. The error flag
PDLCTR.ERRx must be cleared by software.
!
Means not
Re
Means rising edge
Fe
Means falling edge
Forward
ReS1*!S2*S3 + FeS3*S1*!S2 + ReS2*S1*!S3
+ FeS1*S2*!S3 + ReS3*!S1*S2 + FeS2*!S1*S3
Backward
ReS1*S2*!S3 + FeS3*!S1*S2 + ReS2*!S1*S3
+ FeS1*!S2*S3 + ReS3*S1*!S2 + FeS2*S1*!S3
Error
The input signal states S1*S2*S3 and !S1*!S2*!S3 are not allowed
Position
Forward_Counter - Backward_Counter
MCT05923
S1
S2
Forward
Backward
Jitter
Jitter