FANUC Robotics America V7865* - Manual (Page 58)

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V7865 Product Manual
VME Bridge
In addition to its PC/AT functions, the V7865 has the following VME features:
The Tundra Tsi148 allows VME to run at a bandwidth of up to 320MB/s along the full
length of a 21-slot backplane. This increases the performance in the following ways:
• 2eSST VME transfers
• 8x faster than the 40MB/s transfer rate of VME64
• 3x faster than a multi-domain, 64-bit/66MHz CompactPCI bus
• Broadcast Mode support for sending data to multiple cards at one time
Other standard features include:
• Legacy protocol support
• User-configured interrupter
• User-configured interrupt handler
• Full VME system controller functionality
• Two programmable DMA controllers
• System Controller auto detection
The V7865 VME interface is based on the high performance PCIX-to-VME interface
from the Tundra Tsi148. Providing a 64-bit bus width capable of operating at
100MHz, the Tundra Tsi148 uses PCI-X version 2.0 mode 1. Tsi148 is fully compliant
with both 2eSST and VME64 Extension standards.
The functions and programming of the Tsi148-based VME interface are addressed in
detail in the Tsi148 PCI/X-to-VME Bus Bridge User Manual.
PCI-X To VME Bridge (Tsi148) Software Guidelines
Programmers writing code or using GE Fanuc Embedded Systems Board Support
Packages for the Tsi148 Bridge as used on the V7865 Single board Computer, must be
aware of requirements of the Tsi148 based PCI-X to VME architecture.
The V7865 PCI-X to VME Interface uses the Tundra Tsi148 2eSST Bridge. This
architecture interfaces the VME to the onboard SBC PCI-X bus. In doing so, the user
must be aware of the following guidelines as related to Software programming of the
Tsi148:
Shared V7865 Memory : Any V7865 DRAM memory made available to another VME
master through the Tsi148 is subject to dead lock that may cause a VME bus error
unless specific precautions are taken. If onboard DRAM memory is slaved to the
VME, and a program on the V7865 with slaved memory attempts to write (from the
processor) to the VME through the Tsi148, then the user must first request ownership
of the VME through the Device Wants Bus (DWB) Bit in the Tsi148, and be granted the