Installation and Configuration
Npaq MR Hardware Manual
2.6.1. Position Synchronized Output (PSO)/Laser Firing
The PSO can be programmed to generate an output synchronized to the feedback position and is typically
used to fire a laser or sequence an external device. Trigger signals may be derived from a feedback channel
or a software trigger. The position synchronized output pulse is generated using high-speed hardware,
allowing minimal latency between the trigger condition and the output.
An RS-422 line receiver or opto-isolator is recommended, especially when using long cable lengths in noisy
environments or when high frequency pulse transmission is required. It is best to locate the line receiver or
opto-isolator close to the receiving electronics.
N O T E :
The PSO feature is
not
compatible with the -MXU option. The PSO feature operates with the -
MXH option and with square wave encoders.
Table 2-30:
PSO Specifications
Specification
Value
Maximum Input Tracking Rate
(1)
Single-Axis Tracking
16.6 MHz
Dual-Axis Tracking
(3)
8.33 MHz
Maximum Quadrature Encoder Output
Frequency
Standard Feedback
40 MHz
-MXH Feedback
(3)
25 MHz
Maximum PSO Output (Fire) Frequency
(2)
12.5 MHz
Firing Latency
Single-Axis Tracking
160 nsec
Dual-Axis Tracking
(3)
220 nsec
1.
Signals in excess of this rate will cause a loss of PSO accuracy.
2.
The optocoupler that you use on the output might have an effect on this rate.
3.
Npaq MR with ML drives
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Chapter 2
47
