Rockwell Automation 57C650 AutoMax Programming Executive Version 3.8 - Manual (Page 256)

HĆ2 AutoMax Programming Executive Version 3.x
9. Each slot has 64K of address space. Foreign modules that have more
memory can be addressed in the rack if the proper number of slots to the
right of the foreign module are left empty. For example, a foreign module with
128K of memory can be used fully by leaving the slot to the right of the
foreign module empty (64K + 64K = 128K total).
10. Foreign I/O modules that drive pins 24 and 26 on the bus cannot be used in
the rack.
11. All modules in local racks must respond to requests on the bus within 10
µ sec. All modules in remote racks must respond to requests on the bus within
3 µ sec.
Software Requirements
For use in local racks, the foreign module must support 20Ćbit address lines.
For use in remote racks:
1. The foreign module must support 20Ćbit address lines;
2. The foreign module must support 16Ćbit data transfer only;
3. The foreign module must be memoryĆmapped, not I/O mapped;
4. The foreign module address must begin on a 64K boundry.
Accessing Foreign Modules
If a foreign module meets all the hardware requirements and software
requirements above, it can be used in an AutoMax rack. For local racks, the
method of accessing the foreign module depends upon further software
specifications of the foreign module. There is only one method of accessing a
foreign module in a remote rack.
Accessing a Foreign Module in a Local Rack
Method A
Requirements:
1. The module must be capable of 16Ćbit data transfers.
2. If it is an output module, it must be able to respond to read as well as
write commands from the AutoMax Processor.
3. Addresses must begin on a 64K boundry.
4. Input and output registers must be a separate addresses.
Reference to the appropriate variable names in application tasks.
Method B
No requirements beyond the Hardware Requirements and Software
Requirements listed above.
Access the module through BASIC IOWRITE and IOREAD statements in
application tasks.
Accessing a Foreign Module in a Remote Rack
No requirements beyond the Hardware Requirements and Software
Requirements listed above.
Reference to the appropriate variable names in application tasks.