106/132 Operation
Bosch Rexroth AG
, SYEPS series 1X, RE 30201-B/07.2014
When programming the Profibus communication on the CNC/PLC side, please
note that the CNC, PLC and HNC100 are not synchronized and it is not exactly
defined, when the HNC100 will receive data. To make sure that the HNC100
receives new data in due time before the next punching stroke is performed,
handshake protocols should be programmed in the communication between
CNC ⇄ PLC and PLC ⇄ HNC100. This can be ensured with the help of the
acknowledge and error bits, which are sent by the HNC100 to the PLC. In the
data word “Acknowledge bit“ each data word comprises a bit that toggles when a
new value is transmitted in this data word over Profibus. The 1st data word to
the HNC100 (R454 “new mode“) is assigned bit 0, the 2nd data word bit 1, etc.
The assignment is identical in the data word “Error bits”. This means that when
an error is detected while receiving the value transmitted in the 1st data word to
the HNC100 (R454 “new mode“), the HNC100 does not accept the value and sets
bit 0 to 1. By checking the data word “Error bit” for = 0 you can see whether a
transmitted value was taken over or not by the HNC100. In this way, both data
words together make sure that the values were correctly transmitted to the
HNC100.
NOTICE:
Undesirable operational states!
Non-synchronized parameter data transmission to the HNC100 without handshake
can result in undesirable operational states which can also cause a collision on the
machine in the worst case, because position and velocity values are not received by
the HNC100 in due time.
▶
Synchronize the transmission of parameters!
Profibus protocol
The protocol for NC punching machines implemented in the HNC100 looks as
follows. It can be changed with the help of the HNC100 Bus manager and adapted to
suit the individual requirements of the customer. More details are described in the
online help in the HNC100 Bus manager. 32 bytes can be sent by and to the HNC100.
Table 29: Data from the HNC100
Data word
A-variable
Decimal places
Meaning
1
Acknowledge bits Profibus
2
Error bits Profibus
3
A002
0
Error
4
A001
2
Actual position value
5
A003
0
Operating mode
6
A004
2
Following error(k)
