Rice Lake PR5230 Fieldbus Transmitter - Manual (Page 195)

PR 5230 Instrument Manual Fieldbus Interface
Sartorius EN-195
Example: Reading the Gross Weight
The master writes value 8 in
Read_Value_Select (byte 4) of the input area.
Input area
Byte Value Description
0
1
2
3
4 8 Gross
5
6
7
The master waits, until value 8 was reflected in Read_Value_Selected (byte 4) of the output area.
Output area
Byte Value Description
0 00 Gross value
1 00 "
2 4 "
3 D2 "
4 8 Gross weight request
was detected
5 Status
6 Test
Active Command status
7 Stand-
Still Inside
ZSR Center
Zero Below
Zero Over-
load Above
Max Adu
Error Device status
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
The gross value (hex:000004D2 <=> 1234) can be read from bytes 0...3. When the 'Overload' , 'Test Active' or
'ADC error' bits are set, the read value is invalid.
Negative values are output in two’s complement.
9.3 Special hints for DeviceNet and EtherNet-IP
With these field bus types, the sequence of the bytes (only applicable for words and individual bytes) is
inverted.
With long words, this problem does not arise due to compensation by the firmware.
Sequence of bytes 0…3, e.g. with device type and software version, see table:
Standard sequence Sequence for DeviceNet and EtherNet –IP
Byte 0 TYPE MSB Byte 0 SUBVERSION
Byte 1 TYPE LSB Byte 1 MAINVERSION
Byte 2 MAINVERSION Byte 2 TYPE LSB
Byte 3 SUBVERSION Byte 3 TYPE MSB
Consequently, the sequence on the PLC side must be changed when using the DeviceNet and EtherNet –IP field
bus types.