Review

Whether used alone, or as a component in a larger system, or as one of several related modules stacked together to create a more complex system, PC/104 modules continue to grow in power and versatility. The improved performance, in turn, is opening up new applications for these cards. The present batch of new PC/104 cards—like those of previous years—are designed either to add to the processing power and performance of existing families or to broaden the special capabilities available with these cards. As a result, PC/104 cards are available today with just about every function found on pc boards, including CPU, I/O, video, GPS, wireless communication, and a host of other capabilities. A sampling of this year's innovative additions to the PC/104, as well as PC/104-plus, card families is given below.

The PPC/104-555 module from Parvus (parvus.com) is said to be at home in control-intensive applications where timing and control of moving parts is critical. Powered by a 32-bit MPC555 PowerPC processor, the PC/104 module supports 488 KB of flash, up to 32 MB of external flash, up to 4 MB of SRAM, and 1 MB of EEPROM. It also includes 32 configurable I/O channels, two CAN 2.0B modules, two RS-232 ports, an alphanumeric LCD port, and a timing system. And its operating temperature range extends from −40°C to +85°C.

Single-board computers (SBCs) are alive and well in the PC/104 arena. An example is the Jaguar PC/104+ card from Versalogic (versalogic.com). The speedy SBC packs 10/100 Ethernet with a remote boot option, AGP video/flat panel support, a bootable disk-on-chip flash socket, and I/O ports protected from ESD with transient voltage suppressors. It employs a two-board design that can be powered by 350 or 566 MHz Celeron or 850 MHz Pentium III processors, with the 350 MHz CPU operable without a cooling fan. And the SBC can be used alone or with PC/104 or PC/104+ expansion modules and is software-compatible with Windows, QNX, Linux, RT-Linux, and other popular RTOSs.

Motion control is the forte of Navigator-PC/104, a card developed by Performance Motion Devices (pmdcorp.com) for keeping dc brushed and brushless motors and steppers in line with from one to four axes of control. The PC/104 card provides trajectory generation, servo-loop closure, quadrature signal input, motor output signal generation, and trace features and also supports on-the-fly modifications. Motion profiles include S-curve, trapezoidal, velocity contouring, electronic gearing, and user-specific profiles. The board also provides 16 general-purpose digital I/Os and eight analog inputs.

Large quantities of digital I/O lines for PC/104-based systems are available in boards such as the MPC196 from Micro/Sys (embeddedsys.com). The card offers 96 TTL I/O lines, and by stacking three of them together on a PC/104 expandable CPU, the number of I/O lines available to the system can be increased to 288. A second board, the MPC148, provides 53 uncommitted lines of TTL I/O, three 16-bit timers, an octal DIP switch, and eight LED indicators. Both boards employ an 82C55 architecture as the programming interface. All discrete I/O lines have user-selectable pull-ups or pull-downs, with series resistors used to guard against damage.

Based on Virtex-II FPGAs, Derivation Systems's (derivation. com) PF3100 family of PC/104+ modules feature a bus bandwidth up to 132 MB/s. The modules provide a choice of on-board or host configuration, 64 user-configurable I/O pins, an 8-bit FPGA configuration interface, 64 MB of SDRAM, 4 MB of flash memory, and on-board oscillators. Software support includes DOS, Windows 95/98/NT/ 2000/XP, Linux, and QNX 6.x.

—Joe DelGatto

Outlook

Chips And Stacking Further Enhance Performance
Future advances in the performance of PC/104 modules will come through the integration of new processor, video, communications, and other ICs into the small, 3.6" x 3.8" form-factor cards, or by adding modules having dedicated features, such as wireless communications and multimedia capabilities, to an existing stack of general-purpose and dedicated PC/104 cards. The same is expected for PC/104-Plus modules—PC/104-Plus essentially represents a PCI bus addition to the PC/104 standard and is designed to offer improved system performance. These new modules should deepen the application of these cards in manufacturing plants, laboratories, vehicles, and a number of other markets.

—JDG