What Is Lecnet - AKG AS8 Bedienungsanleitung

What is LecNet?

Introduction Introduction Introduction
Introduction Introduction
AKG's LecNet system is a unique implementation of standard RS-232 serial communications. Since
it is compatible with RS-232 serial ports found on all PCs, no extra interface cards are necessary to
add computer control to your LecNet equipment. Unlike standard RS-232 equipment, where one
serial port connects to only one device, as many as 127 LecNet devices may be simultaneously
connected to a single serial port.
LecNet devices can always receive information from the host. In this way, each LecNet device
"listens" for its unique network address. When a device detects its address, it closes its Device Tx
switch to reply to the host. The Device Tx switch is held closed until the data exchange with the
host is complete, and the device opens the Device Tx switch. In this way, device contention is
avoided. Each LecNet device must have a unique address between 128 and 254. Any device
address is reassignable using the LecNet Master Pro application.
The LecNet runs at a fixed rate of 9600 baud, which is not user adjustable. This is fast enough to
provide quasi-real time response to the control panels while providing reliable communications
over reasonable distances (100 feet from host to LecNet device). The serial communications pa­
rameters used are 8 data bits, no parity, 1 stop bit.
L L L L L ecNet Hints ecNet Hints ecNet Hints
ecNet Hints ecNet Hints
Connecting LecNet devices to a host using the LecNet is straightforward. Using the special LecNet
RS-232 cable, simply connect either Com1 or Com2 on the host to the LecNet 3.5mm input on one
of the LecNet devices. If a custom length cable is necessary, refer to chapter 8 in this manual for
the cable connection schematic. The host-to-device connection assumes that multiple LecNet
devices (if more than one are used) are interconnected using the 8 pin expansion cable (AKG IC
AS8).
If more than one LecNet device is connected to the host, all LecNet devices must be powered on
to avoid crashing the network. This is because an unpowered device loads the Host Rx line and
prevents other LecNet devices from communicating with the host. No damage will occur if all
devices are not powered on, and proper operation will resume when all devices are powered.
While AKG has made every effort to make the serial communications software as compatible as
possible with a wide range of serial ports, some serial ports are not well behaved. Some problems
occur with older serial ports, because they may not be reliable at 9600 baud or higher. Software is
available (from Norton, for example) which will test serial ports and determine the highest reliable
data rate.
To run LecNet compatible devices by LecNet you need the LecNet Master Pro Program and the
program for the specific device. Having installed your LecNet Master Pro you simply install the new
device program for your new device, by copiing the file into the LecNet directory.
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