B: typical start-up procedure – INFICON PSG55x ATM to Medium Vacuum Gauge (DeviceNet) User Manual
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40
tira58e1-a (2012-03) PxG5xx.cp
00 00 CA 42
h
(4-Byte, floating format)
42
h
CA
h
00
h
00
h
0 1 0 0 0 0 1 0
b
1 1 0 0
1 0 1 0
b
0 0 0 0
0 0 0 0
b
0 0 0 0
0 0 0 0
b
0 1000
0101
b
100 1010 0000 0000 0000 0000
b
-1
0
1+
23
b
2
0000
0000
0000
0000
1010
100
= 1+
4849664
8388608
d
d
Sign =
Exponent =
Mantissa =
1
133
1.578125
1
Ч
2
(133-127)
Ч
1.578125 = 101
The start up of a device is divided into the steps:
• Allocation
process
• Setting of the EPR attribute
• Choice of the input and output assemblies
Send an allocation string as defined in the DeviceNet specification to the device
you want to allocate.
Set the bits in the allocation choice byte to 1 for these connections you want to use.
Example
Number received
1. Convert sequence of the
HEX words
2. Separate into bytes
3. Calculate
Converted number
B: Typical
Start-Up
Procedure
Allocation process
Sign
8-Bit exponent
23-Bit mantissa