Delta Tau Geo MACRO, Руководство пользователя и справочное руководство

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Geo MACRO Drive User Manual
150 Geo Macro Drive MI-Variable Reference
does nothing – software-1/T functions can still be used. However, it is strongly recommended that MI919
be left at 0 in this case, to prevent possible problems when copying a configuration to newer hardware.
When the hardware-1/T functionality is enabled, the IC computes a new fractional-count position estimate
based on timers every SCLK (encoder sample clock) cycle. This permits the fractional count data to be
used for hardware capture and compare functions, enhancing their resolution. The sub-count position-
capture data can be used automatically in Turbo PMAC triggered-move functions if bit 12 of Ixx24 is set
to 1. This is particularly useful when the IC is used with a high-resolution analog-encoder interpolator
option. However, it replaces the timer registers at the first two “Y” addresses for the channel with
fractional count position data, so the traditional software-1/T method of the conversion table cannot work
if this is enabled.
If the hardware-1/T functionality is enabled and to be able to use 1/T interpolation in the servo loop, use
the hardware-1/T extension method ($C method digit with the mode switch bit set to 1) in the encoder
conversion table.
MS{node},MI921 Flag Capture Position (Read Only)
Range: $0 - $FFFFFF
Units: counts
Default: 0
This variable, when queried, reports the value of the captured position for the machine interface channel
mapped to the specified Geo MACRO Node. Refer to the Motor command/status flag registers for their
relationship to this value.
MS{node},MI922 ADC A Input Value (Read Only)
Range: $000000 - $FFFFFF
Units: Bits of a 24-bit ADC
MI922 reports the value of the serial ADC input register A for the machine interface channel mapped to
the specified Geo MACRO Node number. The value is reported as a 24-bit number, even though there
are a maximum of 18 real bits in the register (the most significant bits) and existing hardware provides 12
or 16 bits of true input.
MS{node},MI923 Compare Auto-Increment Value
Range: -8,388,608 - 8,388,607
Units: Encoder counts
Default: 0
MI923 specifies the value of the position-compare auto-increment register for the machine interface
channel mapped to the specified Geo MACRO Node number.
MS{node},MI924 ADC B Input Value (Read Only)
Range: -8,388,608 - 8,388,607
Units: Bits of a 24-bit ADC
MI924 reports the value of the serial ADC input register B for the machine interface channel mapped to