HVAC Control in the New Millennium.pdf - HVAC.Amickracing

PC-based Control, Software and Bus Trendsa parallel port, 4 IDE interfaces, a floppy drive interface, keyboard andmouse interface.Pentium II/III Computer TrendsThe Intel 440BX chipset can be used in industrial single boardcomputers with a 450-MHz CPU and 768-MB SRAM system memory.The cache memory is integrated in the CPU. An ATI RAGE XL AGPgraphics chipset provides up to 8 MB SDRAM for graphics. I/O mayinclude serial and parallel ports, interfaces for hard disk drives, interfacesfor floppy disks, keyboard interface and DiskOnChip to 144 MB.Cyrix-based ComputersTrends include Pentium MMX-class processors with VGA/LCDinterfaces, audio, 10/100Base-T Ethernet, CompactFlash card socketsand connectors for up to 64 MB of RAM. Low power consumption leadsto a smaller, fanless design and a two-chip Cyrix processor can use lessreal estate than an Intel architecture. Many systems are bundled with theWindows CE operating system. These single-board computers provideparallel and serial ports, USB connectors, keyboard connector and aninfrared port. They can be operated in harsh environments where solidstatestorage and small size are desired.LCD ComputersCombining a 233-MHz Media GX processor, 12.1-inch flat-paneldisplay, resistive touchscreen, 3-GB hard drive and Windows, theWebLink PC provides a platform for control applications. This computerhas 32 MB of RAM, 10Base-T Ethernet port, serial port, parallel port,expansion slots, and a NEMA-4 front panel. The WebLink PC is designedfor space-limited plant-floor applications.Windows CE ComputersIndustrial computers also have full-size SVGA color LCD panelswith touchscreen capability running the Windows CE operating system.©2001 by The Fairmont Press, Inc. All rights reserved.