Product Data Sheets (pdf)...USB Hubs
RS-232 to RS-485/422 Bidirectional Converter Plus Rackmount Card
Installation and User Guide (Feb-98)
Black Box Explains... Advantages of the MicroRACK system.
Product Data Sheets (pdf)...SCSI Differential Converter, SE/LVD to HVD Wide
Product Data Sheets (pdf)...G.703 75-to 100120 Ohm Adapters
Product Data Sheets (pdf)...Relay/Digital I/O Cards, PCI
Product Data Sheets (pdf)...Async RS-232 to RS-422 Interface Converters
Product Data Sheets (pdf)...ISA Cards
• Midplane architecture—Separate front and rear cards make changing interfaces easy.
• Multiple functions—Supports line drivers, interface converters, fiber modems, CSU/DSUs, and synchronous modem eliminators.
• Hot swappable—MicroRACK Cards can be replaced... more/see it nowwithout powering down, so you cut your networks downtime.
• Two-, four-, and eight-port MicroRACKs—available for smaller or desktop installations. Theyre just right for tight spaces that cant accommodate a full-sized (16-port) rack.
• Optional dual cards—Some Mini Driver Cards have two drivers in one card. One MicroRACK chassis can hold up to 32 Mini Drivers!
• All standard connections available—DB25, RJ-11, RJ-45, fiber, V.35.
• Choose you own power supply—120240 VAC, 12 VDC, 24 VDC, or 48 VDC. collapse
Black Box Explains...IRQs, COM Ports, and Windows
Windows® 95 normally requires each serial port to have its own unique Interrupt Request Line (IRQ). However, if you use a third-party communications driver that supports IRQ sharing, you can... more/see it nowshare interrupts. Unfortunately, data throughput will not be as high as with single interrupt port configurations.
With Windows NT®, you can share interrupts across multiple ports as long as the serial ports have an Interrupt Status Port (ISP) built into the card.
The Interrupt Service Routine, a software routine that services interrupts and requests processor time, reads the ISP and is immmediately directed to the port that has an interrupt pending. Compared to the polling method used if the serial ports don’t have an ISP, this feature can determine which port generated the interrupt up to four times more efficiently—and it almost eliminates the risk of lost data. Windows NT supports the ISP by enabling the user to configure the registry to match the card’s settings. Black Box models IC102C-R3, IC058C, and IC112C-R3 all have ISPs and come with a Windows NT setup utility to simplify installation and configuration.
If your serial port doesn’t have an ISP, the Interrupt Service Routine has to poll each port separately to determine which port generated the interrupt. collapse