Allen-Bradley 1747-OC Series, User Manual

Page: 19 / 126

1747-UM001A-US-P - March 2000
Introducing the Open Controller 1-7
DOS API considerations
An application using the open controller DOS API on the 1747-OCE must
select an unused 8K byte memory window address and interrupt line for the
local I/O scanner. These values are passed to the API in the
OC_OpenScanner function call. For example, the following statement
would configure the memory window at C800:0000H, and select interrupt
request 11:
OC_OpenScanner(&Handle, 0xC800, 11)
When running on the 1747-OCF, the memory window and interrupt
parameters are ignored. The OC_OpenScanner function will first search the
PCI bus for the local I/O scanner, and the values that were allocated by the
BIOS are used. This allows you to use the same code for both open
controllers since any parameters entered for the 1747-OCE will simply be
ignored if you are using a 1747-OCF.
The open controller DOS API version 1.04 has been modified to support the
1747-OCF. The DOS API is a static library; therefore, any applications
developed with earlier versions (1.03 and earlier) of the DOS API will have
to be re-linked with the updated API in order to be used with the 1747-OCF.
Contact Rockwell Automation Technical Services for information about
updating your API software.
Windows NT API considerations
The open controller Windows NT API consists of two components:
•
a device driver
•
a DLL
The device driver is responsible for allocating the dual port register (DPR)
memory window and interrupt. The device driver searches the PCI bus for
the 1747-OCF scanner and uses the resources allocated by the BIOS.
The NT API functions are contained within a DLL. It is not necessary to
make any changes to or re-link existing 1747-OCE applications that will be
used on the 1747-OCF, unless unsupported API functions are used (see
Summary of API Differences later in this chapter). All that is required is
that the new device driver and DLL be installed (version 1.03 or later of the
NT API). Contact Rockwell Automation Technical Services for information
about updating your API software.
Allen-Bradley HMIs