X marks the spot

Electronics Times, Nov 30, 1998

With large amounts of asynchronous interrupts, handling such I/O calls can take up to 75% of the host processor bandwidth, says Pauline Shulman, senior market development manager for I2O technology at RTOS developer Wind River Systems.

I2O was first developed by Intel using the i960 risc processor, but PowerPC has been used for an IOP, and Intel is believed to be planning to use the StrongArm processor as the next generation of IOP.

At the Embedded Systems Conference in San Jose earlier this month, Wind River demonstrated calls into VxWorks running on an x86 to interface directly to the its IxWorks operating system running on the IOP. The x86 now accounts for 12% of the host processors for VxWorks and that is growing, says the company.

"The target is anyone today that wants to do an embedded Pentium application with the PCIbus," said Shulman. "They should ask themselves why should they re-invent a whole new messaging protocol. This provides the software stack for PCI-based systems, and saves months and months of development.

"We are now using i960, then if there is a move to StrongArm, if you go on IxWorks all you have to do is recompile."

One of the leaders in I2O, Cyclone Microsystems, has just launched a 64bit PCI system board for building embedded and real-time systems that includes an IOP.

In a mini ATX form factor, the SB-923 has eight slots for 64bit PCI I/O cards on two independent 64bit PCI buses, both hosted by Intel's i960RN I/O processor. This provides an internal 64bit bus and a 528Mbyte/s SDRAM controller that opens I/O bottlenecks, enabling new levels of data throughput for embedded applications.

Because the board boots from 2Mbyte of flash, the need for disk drives, inherent to PC motherboards, is removed. This makes system development and deployment much simpler and more reliable than a PC motherboard.

While PC motherboards also offer cost-effective solutions, many go out of production and become obsolete in six to nine months. The Cyclone board design guarantees product availability for seven years, meeting another of the key requirements of the embedded market with the x86 architecture.