Parallel port strobe and data bits – Rockwell Automation 2706-DXX Dataliner Message Display DL5 Series User Manual
Page 76

2706-UM001A-US-P
9-4
Using the Variable Data Feature
Parallel Port Strobe and Data
Bits
The DL5 uses the sixteen data lines (D0 through D15) to input both variable
data and message triggers. Data lines D0 through D13 transfer the fourteen
data bits and data lines D14 and D15 are the two strobe lines.
The strobe lines indicate whether the data on the data lines is a message
number or variable data. There are four possible combinations of the two
strobe lines. The table below lists the four strobe combinations and the
DL5’s interpretation of the strobe commands.
Strobe Commands
Notice that if data line D15 is ON, the DL5 will interpret the data on the
data lines as a message number regardless of the condition of data line D14.
Strobe Command
Strobe Line, Data Line D14
Strobe Line, Data Line D15
Ignore Data Lines
OFF
OFF
Variable Data
ON
OFF
Message Number
OFF
ON
Message Number
ON
ON