B&B Electronics VFG3000 - Manual User Manual
Page 323
F
UNCTION
R
EFERENCE
P
ORT
I
NPUT
(
PORT
,
START
,
END
,
TIMEOUT
,
LENGTH
)
R
EVISION
1
P
AGE
307
P
ORT
I
NPUT
(
PORT
,
START
,
END
,
TIMEOUT
,
LENGTH
)
A
RGUMENT
T
YPE
D
ESCRIPTION
port
int
The raw port to be read.
start
int
The start character to match, if any.
end
int
The end character to match, if any.
timeout
int
The inter-character timeout in milliseconds, if any.
length
int
The maximum number of characters to read, if any.
D
ESCRIPTION
Reads a string of characters from the
port
indicated by port, using the various other
parameters to control the input process. If
start
is non-zero, the process begins by waiting
until the character indicated by this parameter is received. If
start
is zero, the receive
process begins immediately. The process then continues until one of the following conditions
has been met…
•
end
is non-zero and a character matching
end
is received.
•
timeout
is non-zero, and that period passes without a character being received.
•
length
is non-zero, and that many characters have been received.
The function then returns the characters received, not including the
start
or
end
byte. This
function is used together with Raw Port drivers to implement custom protocols using Fieldbus
Gateway Manager’s programming language.
F
UNCTION
T
YPE
This function is active.
R
ETURN
T
YPE
cstring.
E
XAMPLE
Frame := PortInput(1, '*', 13, 100, 200)