FieldServer FS-8700-115 - Manual (Page 3)

FS-8700-115 ASCII Driver (General Purpose) Page 3 of 13
FieldServer Technologies 1991 Tarob Court Milpitas, California 95035 USA Web: www.fieldserver.com
Tel: (408) 262 2299 Fax: (408) 262 2269 Toll Free: (888) 509 1970 email: [email protected]
GPA (GENERAL PURPOSE ASCII) DRIVER DESCRIPTION 1
The serial GPA (General Purpose ASCII) Driver allows the FieldServer to accept data from remote devices which
produce an ASCII byte stream. A typical example of such a device is an electronic scale producing an output similar
to the one below.
:weight 0.57 Kg Tare 44.3 Kg 1 2 3 4 -5 -6.7
The driver waits passively for messages. When a message is received the driver converts each space delimited
string of characters/numbers into a number. The numbers so formed are stored in consecutive elements of a Data
Array. Referring to the example above, the driver will store the value .57 in the 1
st
element of the Data Array (DA),
the value 44.3 in the next element, the value 1 in the next, the value 2 in the next etc.
The driver is also capable of sending custom poll message to a remote device. Some devices may require a
character or stream of characters sent to it before it will output its data on a serial port.
The driver can process negative numbers.
1.1 Driver Limitations
Only one data stream per connection - if two different streams of string data are sent to the same port, the
data from the one will overwrite data from the other.
The driver can only process numbers that are presented in a simple numeric form. Hexadecimal, Exponent-
mantissa and other complex forms cannot be processed.
The driver will overwrite the existing values with the new values. Values will be appended only if the new
message has more values than the previous message, e.g. if a message with 5 values follows a message
with 3 values, the first 3 values will be overwritten and the last two values will be appended.
Max Nodes Supported
FieldServer Mode Nodes Comments
Client
1 Only 1 node per port.
Server The driver cannot serve data
DRIVER SCOPE OF SUPPLY 2
2.1 Supplied by FieldServer Technologies for this driver
FieldServer Technologies PART # Description
FS-8915-10
UTP cable (7 foot) for Ethernet connection
FS-8915-10 UTP cable (7 foot) for RS-232 use
FS-8917-02 RJ45 to DB9F connector adapter
FS-8917-01 RJ45 to DB25M connection adapter