Allen-Bradley 1747-OC Series, User Manual

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1747-UM001A-US-P - March 2000
1-6 Introducing the Open Controller
Compatibility Issues The 1747-OCE and 1747-OCF are compatible with Allen-Bradley 1746
chassis, I/O and power supplies, as well as existing open controller optional
modules and application code, except as noted in this section.
This section describes the major functional differences between the
1747-OCE and the 1747-OCF. The main focus is on differences that may
affect software developers, primarily as it relates to accessing the local I/O
scanner.
Open controller PCI-based option modules
All open controller option modules are compatible with the 1747-OCE and
the 1747-OCF, expect as noted in the following table:
Resource
allocation
The open controller CPU interfaces with the local I/O scanner through an
8K byte dual port RAM and an interrupt request line. The most significant
difference between the two open controllers is how these resources are
mapped into the system.
On the 1747-OCE, the local I/O scanner interface is ISA-bus based which
requires you to configure the memory window and interrupt through
software.
The 1747-OCF scanner uses the PCI bus. The memory window and
interrupt are allocated by the system BIOS at system startup.
This revision level Of this option module
Is compatible with
this open controller
ALL rev. levels A-B Communications Module
cat. no. 1747-OCKTX/D 1747-OCE
Rev. D01 and above only A-B Communications Module
cat. no. 1747-OCKTX/D 1747-OCF