Micromod Micro-DCI: 53MC5000 PLC AND PRINTER INTERFACES - Manual (Page 38)

4.6 CONTROL BYTES FOR ALLEN-BRADLEY
The APB Setup Bytes, PLC Control and Status Bytes, PLC Read Control Bytes, and PLC Write
Control Bytes are presented in Tables 4-2 through 4-5. If any Control Byte is changed during
operation, it takes up to 10 seconds to become effective (there is a 10 second interval be-
tween PCS checks for setup changes.)
Table 4-2. APB Setup Bytes for Allen-Bradley
Title Definition Set
By
DDI-A DDI-B De-
fault
Mode It indicates the APB communications functionality as
follows:
0 = Off, 1 = Allen-Bradley
This datapoint should be left at 0 and configured to
a 1 after all of the other control bytes are
configured because setting this datapoint causes
the Allen-Bradley PLC Interface functionality to
start.
User B290 B456 0
Baud
Rate It designates the data transfer rate as follows:
10 = 38400, 9 = 28800, 8 = 14400, 7 = 19200,
6 = 9600, 5 = 4800, 4 = 2400, 3 = 1200, 2 = 600,
1 = 300, 0 = 110 User B292 B458 0
Set-Up It designates the data format transfer protocol as
follows:
0 = 8 bits, 1 stop bit, no parity
1 = 8 bits, 1 stop bit, even parity
2 = 8 bits, 1 stop bit, odd parity
User B293 B459 0
Table 4-3. PLC Control and Status Bytes for Allen-Bradley
Title Definition DDI-A DDI-B Set
By
De-
fault
Self
Address It is the PCS source address used in all messages to
the Allen-Bradley PLC. B670 B646 User 0
Setup
Error It indicates the following: 0 = No Error, 1 = L-words to
read > 32, 2 = C-words to read > 64, 3 = L-words to
write > 32, 4 = C-words to write > 64, 5 = The write
command is not 0 or 8 (0 is Protected Write and 8 is
Unprotected Write), 10 = Scan Time at 0. These error
codes cause DDI channel operation to halt. B684 B660 Soft-
ware 0
Scan
Time It is the PCS time period for the read and write phases
of a PCS-PLC transaction. It is entered as a number
from 1 to 255 which represents 100 to 25,500 ms. (See
Section 3.7.) B685 B661 User 0
Scan
Overruns
Counter* This counter is incremented each time the read-write
phases exceed the specified Scan Time. It indicates the
Scan Time should be increased. (See Section 3.7.) B686 B662 Soft-
ware 0
*User can reset by writing zeros into the datapoints.
53MC9015 53MC5000 PLC and Printer Interfaces
4-4
ALLEN