TARGAS-1 Operation Manual V. 1.02
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Digital Connection Methods
There are two methods of connecting to the TARGAS-1 to view digital data:
1. PC USB port
2. Wireless (if WiFi Option is installed).
USB
A USB cable (Mini-B to Type A) can be used to connect the TARGAS-1 to a host device such as a PC,
laptop or tablet. This cable is supplied by PP Systems with every TARGAS-1. When using a terminal
emulator, the COM port settings to communicate with the EGM-5 are: 19200 baud, 8 bit, 1 stop, no parity,
no flow control
.
Wireless
Not available at this time.
Digital Communication Protocols and Software
Once a connection is made to the TARGAS-1, communication software is needed to read, display, and
record data. This section describes three methods for reading TARGAS-1 data and changing settings: the
TARGAS-1 Command Set, for direct communication using TARGAS-1 ASCII character strings; GAS
Software, for a Windows based graphical user interface with graphing and logging; and Web Pages,
which are available only with the WiFi Option.
TARGAS-1 Command Set
When a computer is connected to the TARGAS-1 using a USB cable, a communication protocol and
command set comprised of ASCII characters and strings allows receipt of TARGAS-1 data and setting of
TARGAS-1 parameters. A terminal emulation program (e.g., HyperTerminal or PuTTY) is generally used
for this, but other custom software may also be used to observe and interact with the TARGAS-1 using
these commands.
Measured data is continuously output by the TARGAS-1. The time interval can be modified using the
Host Measure Interval setting (default is every 1 second).
Sending a command
To initiate a command, the Host (e.g., a PC running HyperTerminal) sends an ASCII string in comma-
delimited format to the TARGAS-1. The command can be sent with or without a CRC-8 (9-bit Cyclic
Redundancy Check). If a CRC-8 is sent, a ‘C’ follows the CRC-8 value.
For example,
Host sends command without CRC-8: S,1,25<CR>
Host sends command with CRC-8: S,1,25,080C<CR>
The CRC calculation includes everything but the CRC itself and the ‘C’ character. In the example above,
the CRC was calculated from the string “S,1,25,”.
The command is processed by the TARGAS-1 after the command string terminator <CR> is received.
