The EasyNet card – a 6
layer printed circuit board – complies with the PCI 2.1 standard. It includes a
PCI-controller chip, a programmable logic device and Bus Transceiver Logic Drivers. The EasyNet
bus, that connects the EasyNet cards is a grounded ribbon cable, including 36 data
and 18 command lines, with a connector distance of approximately 0.3 meters and an overall
loength of 3 meters. All measurements have been made with a distributed clock over the
whole bus with 20 MHz.
Actual measurements were taken in a test environment consisting of 2 Personal Computers with Intel Pentium processors (200 MHz) running Linux as operating system. The measured round trip delay was 4.8 microseconds for Remote Store. Transferring a four megabytes block of data from one PC to the other was done with a bandwidth of 70 megabytes per second with a receiver by using MPI, and a latency less than 10 microseconds was measured. The same test on a DEC Alpha motherboard showed a round trip delay of 6.2 microseconds and a bandwidth of 65 megabytes per second with receiver.
frey@scs.ch