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Appendix B - Profibus
APPENDIX B -
PROFIBUS
B.1.
Operation Mode in PROFIBUS:
ASTAT-XT supports both DPV0 and DPV1.
•
DPV0 (Cyclic) allows:
o
Start and shutdown.
o
Read parameters (write parameters are not allowed via DPV0).
•
DPV1 allows:
o
Everything that DPV0 allows
o
Change the cyclic parameters that display via DPV0.
o
Write to registers.
B.1.1.
Structure of the ASTAT-XT Receiving Frame
The first byte must be 0x5A (90 decimal)
The second byte is as follows:
Bit number:
Function:
Note:
0
Stop
Write ‘1’ for Stop
1
Soft Stop
Write ‘1’ for Soft Stop
2
Start
Write ‘1’ for Start
3 Energy
Save
Write ‘1’ (ON) to turn On.
Write ‘0’ (OFF) to turn Off.
4 Dual
Adjust
Write
Write ‘1’ (ON) to turn On.
Write ‘0’ (OFF) to turn Off.
5 Slow
Speed
Write ‘1’ for Slow Speed
Write ‘0’ for normal Start
6
Slow Speed Reverse
Write ‘1’ for Reverse Direction
Write ‘0’ for Forward Direction
7
Reset
Write ‘1’ for reset
Note:
Bit number 0 is the LSB.
Example:
To send Reset, you first need to send 0x5A followed by 0x80.
B.1.2.
Structure of the ASTAT-XT Transmitting Frame
The return frame contains 20 pairs of bytes (40 bytes total), representing the contents of 20 registers.
Each pair of bytes represents one register; all of the registers are 16 bit numbers.
The first byte represents the high value of the number (the MSB).
B.1.2.1.
Selection of the DPV0 Registers through Data Request (DPV1)
By writing to Slot number 1 and Index 2, you can change the register that appears in DPV0.
Remember that for each register there are 16 bits (two bytes/one word). The first byte represents the high value of
the register number.
To demonstrate this, let’s say that we want to see the following registers in DPV0 (cyclic):
Logic Status
Motor Current
Line Voltage
Hardwired Inputs
Thermistor Resistance
Thermal Capacity
Frequency
Phase Sequence
DIP Switch
Elapsed Run Time