Instruction manual

FUNCTIONAL
SERIAL COMMUNICATION
In general, Milltronics products designed for serial communication transmit data over a bipolar current loop.
This format allows for communication loop lengths of 3000 m (10,000 ft) as opposed to limited runs of 15 m
(50 ft) as afforded by RS-232 or RS-422.
Some Milltronics products use the RS-232 format for direct connection to a computer. To extend the
communication distance, the RS-232 format is converted to the bipolar current loop format using a Milltronics
CVCC (Current to Voltage Communications Converter).
A BIC-II is connected in the loop at a point close to the host computer or PLC to convert the bipolar current
loop to RS-232 or RS-422.
MEMORY
All software set up information is stored in non-volatile memory. Should power to the BIC-II be interrupted, the
BIC-II will resume normal operation once power is restored. In the event of a power interruption, messages
stored are retained for approximately 24 hours. When power is resumed the FIFO buffer is empty.
OPERATING MODES
The BIC-II is capable of operating in three different modes as set by board A switch SW2 - 6 and 8.
BIC MODE
This feature was designed to permit the BIC-II to replace an original BIC with minimal computer software or
PLC programming changes.
This mode emulates the original BIC operation, with the following exceptions :
› time of day messages (most personal computers now have time keeping capability)
› product/BIC-II baud rate is set by the Host/Millbus baud rate selection.
› only the buffered mode is available
In this mode, only product PORT1 of the BIC-II may be utilized. The BIC-II cannot be daisy chained to
an original BIC.
BIC-II MODE
The BIC-II mode permits full access to the 6 product ports, limited only by the total load factor presented by
the products connected.
Complete set up for each product port is received by the BIC-II from the computer or PLC in the form of a Port
Initialization Command.
Communication with all Milltronics products equipped with serial communication is possible in this mode.
PL-371 5 – 1