Almost anyone who has even a rudimentary knowledge and understanding of computers knows what RS232 is, or has at least heard of it. That's because serial data communication, once the primary means of interconnectivity between computers, is still being used today, albeit mostly for hooking up peripherals and instruments. Ask, however, for a description and explanation of RS422, and you'll mostly get blank stares. That's peculiar as RS-422 is a logical progression of RS-232 and one that made a whole lot of sense.
In essence, RS422 (which should really be called by its proper current name, EIA-422) happened due to a number of shortcomings and limitations inherent to the RS232 standard, primarily in the areas of speed, reliability and flow control. If RS232's limitations make it unfeasible for a particular project, RS422 can be a solution as it was designed to handle higher speed (up to 100kbps) and longer distances (up to 4,000 feet) than RS232. In fact, the highest data rate of RS-422 is up to 10 mbps over short distances, which means it rivals USB and Ethernet.
Very often stores sell you a package deal with a monitor included in the package and while it is possible to get a very good quality model monitor, it doesn't often happen as stores take this opportunity to get rid of their old stock. If you are particular about the kind of monitor you want and you should be, shop for your monitor as a separate item.
How can RS-422 connections be faster and operate error-free over much longer distances? That's because instead of using different voltage levels with respect to ground as RS232 does, RS422 uses a "balanced" signal with negative and positive voltages (ranging from -6 to +6 Volts) on twisted pair wires that is far more immune to interference. This is referred to as "differential" data communication because it relies on the voltage difference between the two wires as opposed to a voltage level compared to ground, a technology that makes it much easier for the receiver to recognize ground shifts and noise and reject them before they can introduce errors into the signals.
In addition to speeds up to 10 megabits per second (albeit only over a fairly short distance of 40 feet) and a maximum connection distance of 4,000 feet, RS-422 can communicate in both directions simultaneously. And while the standard only allows for a single driver, there can be multiple receivers (up to 10). RS-422 systems need a dedicated pair of wires for transmitting and receiving, and also one for control signals, if required. Depending on speed, distance and the characteristics of nodes, termination (the matching of impedance between nodes and the line) may or may not be an issue in RS-422 systems.
Even if you are not a techie you can still ask intelligent questions about the motherboard capabilities and make sure that the one you buy has at least 2-3 USB ports in the front for your memory drive or audio player. Additional ports in the back will be helpful for attaching a host of additional equipment like printers and external hard drives. Color coded cables simply the setup and a high end audio and video output with Fire Wire ports should be part of the package. Ask about warranty and technical support, without the right warranty and less than adequate after sales support you will be in trouble. Make use of our guide to help you research the available models and make the right choice. - 22787
In essence, RS422 (which should really be called by its proper current name, EIA-422) happened due to a number of shortcomings and limitations inherent to the RS232 standard, primarily in the areas of speed, reliability and flow control. If RS232's limitations make it unfeasible for a particular project, RS422 can be a solution as it was designed to handle higher speed (up to 100kbps) and longer distances (up to 4,000 feet) than RS232. In fact, the highest data rate of RS-422 is up to 10 mbps over short distances, which means it rivals USB and Ethernet.
Very often stores sell you a package deal with a monitor included in the package and while it is possible to get a very good quality model monitor, it doesn't often happen as stores take this opportunity to get rid of their old stock. If you are particular about the kind of monitor you want and you should be, shop for your monitor as a separate item.
How can RS-422 connections be faster and operate error-free over much longer distances? That's because instead of using different voltage levels with respect to ground as RS232 does, RS422 uses a "balanced" signal with negative and positive voltages (ranging from -6 to +6 Volts) on twisted pair wires that is far more immune to interference. This is referred to as "differential" data communication because it relies on the voltage difference between the two wires as opposed to a voltage level compared to ground, a technology that makes it much easier for the receiver to recognize ground shifts and noise and reject them before they can introduce errors into the signals.
In addition to speeds up to 10 megabits per second (albeit only over a fairly short distance of 40 feet) and a maximum connection distance of 4,000 feet, RS-422 can communicate in both directions simultaneously. And while the standard only allows for a single driver, there can be multiple receivers (up to 10). RS-422 systems need a dedicated pair of wires for transmitting and receiving, and also one for control signals, if required. Depending on speed, distance and the characteristics of nodes, termination (the matching of impedance between nodes and the line) may or may not be an issue in RS-422 systems.
Even if you are not a techie you can still ask intelligent questions about the motherboard capabilities and make sure that the one you buy has at least 2-3 USB ports in the front for your memory drive or audio player. Additional ports in the back will be helpful for attaching a host of additional equipment like printers and external hard drives. Color coded cables simply the setup and a high end audio and video output with Fire Wire ports should be part of the package. Ask about warranty and technical support, without the right warranty and less than adequate after sales support you will be in trouble. Make use of our guide to help you research the available models and make the right choice. - 22787
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