2
System overview
1 System overview
The RPI30 converts 1 Vpp analogue quadrature signals from an RLE
laser interferometer encoder system into a position reading, which is
available over a parallel bus. The RPI30 interface includes active
Sub Divisional Error (SDE) correction, to further reduce the effect of
errors within the motion control system. This is applied by actively
updating the DC offset and AC mismatch when the system is in use to
achieve the highest performance.
Additionally the RPI30 has an separate diagnostics connection to allow
diagnostics information to be downloaded and analysed remotely.
The RPI30 gives an output of both axis position and status over a
LVTTL (3.0 V) compatible bus. The position is available as a 36-bit two’s
complement word, with a choice of least significant bit (LSB) resolution.
The status information includes the signal strength and error flags.
Part numbers
The following saleable part number is available:
• A-9926-0700
RPI30 fast parallel interface
In addition, the mating half of the RPI30 parallel bus connectors can
also be supplied by Renishaw. The saleable part number is:
• A-9904-2256
RPI connector 0°
For information on the connector please refer to Section 2.
RPI30 fast parallel interface