snap ethernet-based i/o units protocols and programming guide

Bytes 0–3
Bytes 4–7
Bytes 8–11
Bytes 12–15
CHAPTER 4: USING THE IEEE 1394-BASED PROTOCOL
for point 32 is at the address FFFFF0A00800. (40 hex x 32 decimal = 800 hex). The Read Quadlet
Request would look like this:
Read Analog Point Data—Read Quadlet Response (Brain➞PC)
The response to your request might look like this in binary notation:
destination_ID tl rt tcode pri
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 1 1 0 0 0 0 0
source_ID rcode reserved
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
reserved
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
quadlet_data
0 1 0 0 0 0 0 1 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
In hex, it would look like this: 00000460000000000000000041780000
The rcode parameter shows an ACK (0), and the quadlet_data parameter, shown in bold type in
the hex version, equals the IEEE float 15.5.
Disconnecting
The connection is kept open during normal communications. Disconnect only when all
communication is complete. To disconnect, OptoEIEIO again uses the Microsoft Winsock control:
tcpIOUnit.Close
Memory map address for point 32 data
in Engineering Units
SNAP Ethernet-Based I/O Units Protocols and Programming Guide 87