Moxa Technologies OnCell G3111-HSPA series, Руководство пользователя

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Introduction to Serial Port Operation
Modes
In this chapter, we describe the various operation modes of the OnCell G3111/G3151-HSPA. The OnCell
G3111/G3151-HSPA modes are grouped by type of application, such as Device Control. The options include an
operation mode that relies on a driver installed on the host computer, and operation modes that rely on TCP/IP
socket programming concepts. After selecting the proper operation mode, refer to
Chapter 7, Serial
Operation Mode Settings , for detailed information on configuration parameters.
Overview
The OnCell G3111/G3151-HSPA cellular IP gateway enables traditional serial (RS-232/422/485) devices for
transmitting data over the cellular network. The IP gateway is a tiny computer equipped with a CPU and TCP/IP
protocols that can bi-directionally translate data between the serial and IP formats. With the OnCell
G3111/G3151-HSPA, your computer will be able to access, manage, and configure remote facilities and
equipment over the cellular network from anywhere in the world.
Traditional SCADA and data collection systems rely on serial ports to collect data from various kinds of
instruments. Since the OnCell G3111/G3151-HSPA cellular IP gateway network-enables instruments equipped
with an RS-232, RS-422, or RS-485 communication port, your SCADA and data collection system will be able
to access all instruments connected to a standard TCP/IP network, regardless of whether the devices are used
locally or at a remote site.
The OnCell G3111/G3151-HSPA is an external IP-based network device that allows you to expand a serial port
for a host computer on demand. As long as your host computer supports the TCP/IP protocol, you will not be
limited by the host computer’s bus limitation (such as ISA or PCI), nor will you be limited if you do not have
drivers for various operating systems.
In addition to providing socket access, the OnCell G3111/G3151-HSPA also comes with a Real COM/TTY driver
and a Reverse Real COM/TTY driver that transmits all serial signals intact. This enables you to preserve your
existing COM/TTY-based software without needing to invest in additional software.
Three different socket modes are available: TCP Server, TCP Client, and UDP. The main difference between the
TCP and UDP protocols is that TCP guarantees delivery of data by requiring the recipient to send an
acknowledgement to the sender. UDP does not require this type of verification, making it possible to offer faster
delivery. UDP also allows you to unicast data to one IP, or multicast the data to a group of IP addresses.