Yaskawa Modicon 800 Series Remote I/O Network for use on Microtrac LAN - Manual (Page 14)

3 SOFTWARE
13 Programming the PAC Blocks
5/24/96
When the PLC gateway receives these messages, it requests a confirmation
from the Modicon PLC to confirm that drop 2 has a B804 module in drop 2,
rack 2, slot 1 and a B865 module in drop 2, rack 2, slot 2. Once this is
confirmed, data can be exchanged.
Node Number
The node number used by the PAC block to address the PLC gateway is
usually 200. It can be any node number in the format 20x.
Format of Numeric Data
Each Channel of a Modicon analog module uses one 16 bit word. The word is
presented to the Modicon PLC as a two’s complement binary number (also
called a signed integer). These numbers can range from +32767 to –32768.
Each integer value has an assumed fixed location for the decimal point (DP).
The assumed decimal point location must be used in both the PAC code and
PLC ladder logic. In the PAC code, the decimal location for a given numeric
is defined by its DP setting. For example, if the integer transferred from the
PLC to a PAC block has a range of +32.767 to –32.768, the DP parameter for
that PAC NUMI block must be specified as three (3).
Format of Logic Data
When entering a discrete module into the Traffic Cop program of the Modicon
PLC, a reference number must also be entered. For discrete output points, the
reference numbers are in the range 00001 to 09999; discrete input points range
from 10001 to 19999. So if a discrete input module (B805) was entered into
the Traffic Cop, 10001 would be entered as the reference number. The PLC
then reserves 10002 through 10016 for the other points in the module. If the
points 10001, 10002 and 10016 are enabled and the rest are disabled, then the
value shown is C001. The bit in 10001 is the most significant bit in that word
and the bit in 10016 is the least significant bit. The MicroTrac LAN message
for allocating and upgrading logic contains a 4 byte mask field. If the bits
within these 4 bytes are labeled 63-0, with 63 being the most significant bit
and 0 the least significant bit, then to address point 10001 requires bit 1 (not
bit 0) to be on, bit 2 for 10002, and so on.
RD 3004-20