Describing the parallel port – Rockwell Automation 2706-LV2P_LV2R_LV4P_LV4R DL40 PLUS USER MANUAL User Manual
Page 83

Parallel Port Communications
7–3
Publication 2706-6.1
The Parallel Port has connections for 4 strobe lines and 16 data lines.
KEYBOARD
SW1
SW2
GND
RELAY
L1 L2N
RS-485
250 VAC 3A
12VDC
RS-232
Parallel Port
The 4 strobe lines (MS0–MS3) specify the type of information on
the data lines (D0–D15).
For Message/Variable/Slave run mode, D0–D15 can receive:
•
message number to trigger
•
slave address to which message will be sent
•
variables to be placed in message
–
16 bit binary
–
4 digit signed BCD
–
l digit unsigned BCD
–
1 character ASCII
For Message List run mode, D0–D15 can receive:
•
priority msg. number to trigger (interrupts message list)
•
message number to add to message list
•
message number to delete from message list
The following shows the relative significance of each data line.
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
MSB (Most Significant Bit)
(Least Significant Bit ) LSB
Describing the Parallel Port