Controlink Systems makes software designed for controlling machining and manufacturing equipment, over RS-232 (the standard interface). Direct Numerical Control (DNC) is used to control machining equipment when the machine itself does not issue the processing commands.
Controlink Systems software meshes nicely with LAVA’s serial interfaces, whether PCI, PCIe, or Ethernet-to-Serial device servers.
Tiba Restaurant Equipment makes high-end consumer and commercial kitchen and restaurant equipment, including hot tables, counters, refrigerators, sinks, and barbeques. Their work consists largely of metalwork design and fabrication, primarily in stainless steel for pieces of equipment, and in galvanized metal for ductwork for installations in restaurants, hotels, banquet halls, kitchens, and residential homes.
Tiba’s metal cutting designs are created on a computer that has patterns and templates, and specialized software for ductwork design. When Tiba is ready to cut material, these designs are sent to Tiba’s Cybermation plasma cutting table, where much of their metal cutting is carried out. The connection between computer and cutting table is RS-232 serial, handled by a LAVA SSerial-PCI card.
Their metal cutting capability is critical to Tiba’s business, and the reliability that comes with a LAVA card is key to their success.
Our popular one- and two-port serial device servers — the Ether-Serial Link 1-232-DB9, the 2-232-DB9, the 1-232-RJ45, and the 2-232-RJ45 — have now been spun into PoE (Power over Ethernet) versions. Because these device servers are designed to draw their power from the same Ethernet cable that is used for their Ethernet interface, there is no need for AC (mains) power. Deployment is greatly simplified, and unnecessary power adapters (“wall warts”) can be eliminated. These four devices are compatible with IEEE 802.3af-2003 at 3 Watts, Mode A operation.
For these PoE Ether-Serial Links to operate, they will need to be attached to a network supplying power over Ethernet, and that’s about it. That power is added to the Ethernet by either a “PoE endspan” or a “PoE midspan” — switches or other devices designed to inject the appropriate power into the network cabling. The cabling used is standard network cabling (assuming it has the usual complement of wires), and no additional software is required to make a working PoE system.
These PoE serial device servers also come with a connector that can be used to supply conventional power through an AC to DC wall adapter, supplied separately.
When it comes to RS-232 electrical characteristics, there is one important thing to note: the voltage range for signalling in RS-232 is very wide, from 3 to 15 volts, plus or minus. The implication is that designers of serial port boards, such as LAVA, have wide latitude for electrical design, according to the specification. In reality, if a board designer takes the minimal approach, their users might run into disappointment. Let me explain.
All LAVA PCIe serial ports are engineered to provide a near-full voltage signalling range on their serial port pins. Specifically, LAVA serial ports comply fully to serial port requirements by generating a voltage range of at least +12V to -12V.
This is important when your serial data rate is high, your cable runs are long, or there is a greater than ideal amount of electrical “noise” in the area. It also matters when the serial peripheral attached makes a draw on the serial port. In those situations the added voltage differential can make the difference between a connection that works and one that doesn’t — just as with a car, you need a little more horsepower when you start to pull a trailer.
PCI and PCIe serial port add-in cards draw their power from the bus on which they are attached. In the case of PCI, there is enough voltage range on the bus to allow a serial port adapter card to operate within the specified voltage range; in the case of PCIe, there is not.
You can see, on all LAVA PCIe boards with serial ports, the little copper induction coil that contributes to this capability. Check out other companies’ products on the web and you’ll see that they have cut corners here: they are in many cases not generating the -12V signal — is the risk to the reliability of your connection really worth it?