Performance Motion Devices Prodigy Series User Manual page 93

• Compatible with any absolute encoders which support the Synchronous Serial Interface (SSI), such as
Haidenhein, Stegmann, Thalheim, and Renishaw encoders that meet the DC-1000's resolution and clock
frequency requirements
Unlike incremental encoders, optical encoders always supply the exact absolute position. At power-on, the encoder
will report its exact position. This precludes the need for the machine to locate a machine reference. Absolute encoders
are grouped into two categories: single-turn and multi-turn. Encoders with a resolution of up to 360 degrees are single-
turn encoders. Those which can resolve several turns (normally up to 4,096) are classified as multi-turn encoders.
The SSI interface requires four data lines, regardless of the encoder's resolution. This is accomplished by converting
the parallel data into serial data. Each bit of the parallel data is the sent on the data lines +/- synchronously to the +/
- clock lines. The clock speed of the DC-1000 is programmable between 1.1 MHz and 137.5 kHz. The clock speed
depends on the length of the data cables between encoder and controller.
The DC-1000 receives, converts, and stores the encoder data in registers. This data can then be read by the Prodigy/CME
PC/104's Magellan Motion Processor. The DC-1000 can be programmed for encoder resolutions of 10, 12, 13 and 25 bits.
The transmission speed may be programmed to accommodate cable lengths of greater than 300 meters, and both single-
turn encoders and multi-turn encoders may be employed. The Prodigy/CME PC/104 card will capture the absolute
position of single-turn encoders for a full 32 bits. When a roll-over occurs, it will be detected by the card and the correct
position will be stored. The direction of motion will also be correctly detected.
5.3.1 DC-1000 Specifications
• Dimensions: 2.75 inches x 2.25 inches
• 40-position mating connector for the Prodigy/CME PC/104 card
• 2 stand-offs with screws for mounting to Prodigy/CME PC/104 card
• Encoder mating connector for 5V DC or 12V DC from PC power supply
• Jumper for selecting 5V or 12V supply voltage for the encoders
• 26-position IDC connector and mating stub IDC ribbon cable
• DIP-switches for setting encoder resolution for each axis
• Four position registers (one for each axis) maintain absolute positions
• All positions may be read by the Prodigy/CME PC/104 card at any time
• Four read and write registers (one for each axis) for programmatically setting resolution and clock speed
• Resolution and clock speed settings can be different for every axis
The following diagram illustrates the location of the DC-1000's main components and connectors. The component
side of the card is shown.
Prodigy/CME PC/104 User's Guide
Interconnect Module
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