B&B Electronics VFG3000 - Manual - Manual (Page 325)

F UNCTION R EFERENCE P ORT R EAD ( PORT , PERIOD )
R EVISION 1 P AGE 309
P
ORT
R
EAD
(
PORT
,
PERIOD
)
A RGUMENT T YPE D ESCRIPTION
port int The raw port to be read.
period int The time to wait in milliseconds.
D
ESCRIPTION
Attempts to read a character from the port indicated by port . The port must be configured to
use a raw driver, such as the raw serial port driver, or either of the raw TCP/IP drivers. If no
data is available within the indicated time period, a value of –1 will be returned. Setting
period to zero will result in any queued data being returned, but will prevent Fieldbus
Gateway Manager from waiting for data to arrive if none is available.
F UNCTION T YPE
This function is active.
R
ETURN
T
YPE
int.
E XAMPLE
Data := PortRead(1, 100)