Delta Tau Geo MACRO, User Manual And Reference Manual

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Geo MACRO Drive User and Reference Manual
Geo Macro Drive MI-Variable Reference 143
(sign) signal on CHBn. If the signal is unidirectional, the CHBn line can be allowed to pull up to a high
state, or it can be hardwired to a high or low state.
If MI910 is set to 8, the decoder inputs the pulse and direction signal generated by Channel n’s pulse
frequency modulator (PFM) output circuitry. This permits the GEO MACRO Station to create a phantom
closed loop when driving an open-loop stepper system.
No jumpers or cables are needed to do this; the
connection is entirely within the ASIC. The counter polarity automatically matches the PFM output
polarity.
If MI910 is set to 12, the timer circuitry is set up to read magneto-strictive linear displacement transducers
(MLDTs) such as Temposonics
TM
. In this mode, the timer is cleared when the PFM circuitry sends out
the excitation pulse to the sensor on PULSEn, and it is latched into the memory-mapped register when the
excitation pulse is received on CHAn.
If MI910 is set to 11 or 15, the channel is set up to accept 3-phase “hall-effect” style inputs on the A, B,
and C inputs, decoding 6 states per cycle.
MS{node},MI911 Primary Enc. Position Compare n Channel Select
Range: 0 - 1
Units: None
Default: 0
0: Use channel n encoder counter for position compare function
1: Use first encoder counter on IC (encoder 1 for channels 1 to 4; encoder 5 for channels 5
to 8) for position compare function
MI911 determines which encoder input that the position compare circuitry for the machine interface
channel mapped to the specified node uses.
When MI911 is set to 0, the channel's position compare register is tied to the channel's own encoder
counter, and the position compare signal appears only on the EQUn output.
When MI911 is set to 1, the channel's position compare register is tied to the first encoder counter on the
ASIC -- Encoder 1 for channels 1-4, Encoder 5 for channels 5-8, or Encoder 9 for channels 9-10 -- and
the position compare signal appears both on EQUn, and combined into the EQU output for the first
channel on the IC (EQU1 or EQU5); executed as a logical OR.
MI911 for the first channel on an ASIC performs no effective function, so is always 1. It cannot be set to
0.
MS{node},MI912 Primary Encoder n Capture Control
Range: 0 - 15
Units: none
Default: 1
This parameter determines which signal or combination of signals, and which polarity, triggers a position
capture of the counter for the encoder mapped to the specified node. If a flag input (home, limit, or user)
is used, MI913 for the node determines which flag. Proper setup of this variable is essential for a
successful home search, which depends on the position-capture function. The following settings may be
used: