Roland R1000 Series Manual page 89

B0048191 / Rev. 1.5
6.4.3 Service "Close parameter channel"
The service "Close parameter channel" is initiated by the master by selecting the service. The
content of the index bytes I1, I2 and the application data bytes 0 through 3 is not relevant. The
checksum of bytes 1 through 6 is calculated and inserted in byte 7. To initiate the service the
master changes the handshake bit.
To avoid data fault the following sequence is compulsory:
1. Service selection, program index, parameter index
2. Switch handshake
In addition consistent data transmission from master is necessary.
The R1000 checks the data with the checksum and mirrors the application data bytes, the service
selection and the index selection in O1, O2. The R1000 sets the handshake bit in O0.0 only in the
last step and signals thereby that the data is valid. This sequence is observed by the R1000 in
order to avoid data faults.
The slave should ensure a consistent data transmission.
6.4.4 Service "Read parameters"
The master initiates the service "Read parameter" by selecting the service, and index bytes I1 and
I2. The content of the application data bytes 0 to 3 is not relevant. The checksum of byte 1 through
6 is calculated and inserted in byte 7. To initiate the service the master changes the handshake bit.
In order to avoid data faults the following sequence is compulsory:
1. Service selection, program index, parameter index
2. Switch handshake
In addition consistent data transmission from master is necessary.
The R1000 checks the data with the checksum and makes the content of the respective
parameters available in the application data bytes of parameter channel O3 ... O6. In addition the
R1000 mirrors the service "Read parameter" and the index adjustment in O1, O2. Only in the last
step sets the R1000 the handshake bit into O0.0 and indicates thereby that the data is valid.
This sequence is observed by the R1000 in order to avoid data faults.
The slave should ensure a consistent data transmission.
ROLAND ELECTRONIC GmbH · Otto-Maurer-Str. 17 · DE 75210 Keltern · Phone +49 (0)7236-9392-0 · Fax +49 (0)7236-9392-33
Double Sheet Detector R1000 series UDK20
with integrated fieldbus interface
Note For the service "Open parameter channel" the index bytes I1,I2 and the
application data bytes I3... I6 are irrelevant.
Attention If the checksum is correct then the closing of the parameter channel is
always executed. A set collision bit is thereby deleted.
Note The application data bytes I3 - I6 of the service "Read parameter" are not
relevant.
Attention A collision bit is set if reading cannot be executed. Instead of
application data the default number is transmitted,
see "6.4.8 Reset faulty access".
Manual
Communication with the PLC
89