Basic SLIO backplane bus Information:

• Single master system
• Up to 64 slave (Node) stations
• Asynchronous, serial data transmission with 48 MBit/s over Point to Point LVDS physic
• Additional alarm line for initialization and asynchronous event communications from node to master
• Full system detection from SLIO master without external information on module configuration
  
  

Error detection mechanism:

• CRC code with Hamming distance 4 for every telegram (all 3 bit errors will be detected)
• Watchdog function inside every node for SLIO master observation
• “Auto shut down” in case of SLIO master malfunction
• Retry statistic for early detection of possible transmission issues
  
  

Time-synchronisation:

• Every node has its own clock with 1μs resolution
• All node clocks are synchronized with the SLIO master (accuracy <100ns)
• Option for clock synchronization from SLIO master to SLIO master via different protocols
  (Profibus DP V2, Profinet, Ethercat,...)
  
  

Technological functions in SNAP+:

• Standard I/O function: 8 digital I/O or up to 32 I/O with shift register
• Integrated digital input filter function
• Asynchronous event signaling with μs time stamping for advanced nodes
• Two advanced counters with AB oversampling, latch, reset, output, hysteresis, comparevalue, repetitive/endless counting and additional time stamp information
• SSI function with time stamp information (speed calculations: counter difference/time)
• Pulse Width Modulation with 20ns resolution
• Frequency measurement mode
• Special digital I/O time stamp nodes (ETS: Edge Time Stamp System) for input edge and output control with 1μs resolution (independent from fieldbus cycle!)
  
  

SPI interface in SNAP+ for analog I/O / safety / serial CP with external MCU:

• 3 MBit/s SPI interface for external microcontroller
• Up to 192 Byte for parameters, up to 16 Byte In / 16Byte Out data for external microcontroller
• Alarm function and watchdog function
  
  

Performance:

• Different „Speed Grades“ for data transmission
• Multinode telegrams for maximum efficiency:
  
  • Write 64 nodes (8 outputs/node): 17μs
  • Read 64 nodes (8 inputs/node): 32μs (with node presence check)Asynchronous event reaction time: 9μs
    
    

Mechanical and electrical specification SNAP+ (preliminary):

• I/O voltage: 3,3V, typ. 16mA, core voltage: 1,8V, typ. 16mA
• DI8 or DO8 modul without I/O load: typical: 5V, 32mA
• LQFP 48 package, 9,0mm², pitch 0,5mm