JX3-BN-CAN
5 Register Addressing
5.2
Indirect Access to JX3 Module Registers
Each JX3 module is equipped with over 10,000 module registers. One index and one
data register make access to all 10,000 module registers possible.
Figure 2: Indirect register access to JX3 modules
Above, indirect access to the JX3 module registers (2) has been illustrated. In the Jetter
system bus, the JX3 modules can be accessed via register numbers 3xxz (1). At indirect
access, the number of the JX3 module register is written to 3xx7. After this, the content of
the JX3 module register can be accessed via 3xx8.
Register Numbering Dependent on the Controller
•
For JC-24x controllers: Register number 3xxz
•
For JC-647 controllers: Register number 3m03xxz
•
For JC-800 controllers: Register number 4CM03xxz
Indirect Register Access in the Application Program
•
Indirect access to JX3 module registers of a module may only be carried out within a
task. If indirect access is made out of several tasks, the index may be overwritten
after a task change.
Jetter AG
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