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Sundance BBK-PCI Light Transputer OS Link Interface for PCI Systems


Transputers are able to communicate via each of its links at full speed without any significant loss of performance. However, transputer links connected to ISA based PCs use a significant proportion of the host CPUs computational power, even if running at sub-optimal transfer rates. The BBK-PCI is designed to eliminate this bottleneck and offers additional benefits by taking advantage of the PCI bus.

The BBK-PCI light acts in busmaster DMA mode as a kind of communication coprocessor. The host is only responsible for setting up the board for a desired communication. As soon as the link is ready to transfer, the bus interface hardware acquires the control over the PCI bus. It transfers a block of data between link and host memory before releasing the bus control. In the meantime the host is free to process other tasks. The completion of a communication is signaled to the host by interrupt. This optimized handling guarantees the transfer rate over the link to be close to the limits of the IMSC011 OS link interface chip. Even where the application does not require very high transfer rates, the host system load level is minimal. With standard interfaces a data stream full of gaps forces permanent attention of the host CPU. The time distance between single bytes in a stream is often too long to wait for the next action and too short to initiate an interrupt cycle. It is always a compromise between system load, transfer rate and response time. So any PCI hosted system can efficiently manage multiple BBK-PCI lights in DMA mode simultaneously.

To use B004 based applications without the need of modification for the use with BBK-PCI light, a B004 register compatible mode is also supplied.

Various link connector type options are available. The link interface and the system services are furnished in both single-ended and differential form.

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