CANISA
CANbus
®
Network Interface Module for ISA Bus Computers
INSTALLATION GUIDE
INTRODUCTION
The CANISA is a Controller Area Network (CAN) adapter for ISA bus
computers. CAN is the data link layer technology used by DeviceNet and
Smart Distributed System. The CANISA supports 8-bit transfers and takes
advantage of the additional interrupts on the expanded bus.
The CANISA incorporates the Philips SJA1000 CAN stand-alone controller
chip which is used widely in both the automotive and general industrial
environments. Besides being backward compatible with the older 82C200,
the SJA1000 has more features than its predecessor. The 82C200 is
restricted to BasicCAN (11-bit identifiers) while the SJA1000 operates in
either BasicCAN or a new mode called PeliCAN™ which supports the CAN
2.0B specification (29-bit identifiers). The SJA1000 maintains extended
frame passivity while in the BasicCAN mode.
The SJA1000 features a 16 MHz clock, a larger receive buffer and better
acceptance-filtering — including the ability to extend the acceptance mask
to the data field. It has the ability to operate at data rates as great as 1 Mbps.
The CANISA incorporates the DeviceNet physical layer with an optically
isolated transceiver providing reverse voltage and short-circuit protection.
Field connectors include the DeviceNet 5-position open style and DB-9 as
defined by CAN in Automation (CiA).
The PeliCAN mode includes:
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Error counters with read/write access
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Programmable error warning limit
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Last error code register
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Error interrupt for each CANbus error
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Arbitration lost interrupt with detailed bit position
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Single-shot transmission (no re-transmission)
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Listen only mode (no acknowledge, no active error flags)
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Hot plugging support (software driven bit rate detection)
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Acceptance filter extension (4-byte code, 4-byte mask)
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Reception of ‘own’ messages (self reception request)