| Vx/1553-[BC|RT-MT] Features Summary
Copyright (c) 1996 Compware Corp.
The Vx/1553 Device Support Package from Compware together
with the ILC/DDC 65528 VME (6U)Quad 1553 Controller provides versatile MIL-1553 operation.
The 65528 employs (1-4) ILC/DDC BU61580 1553 controllers.
Each BU61580 provides 8K of internal RAM and intelligent dual redundant-channel
frame-based (for BC) and subaddress-based (for RT) bus access. The BU61580 provides
multi-channel retry capability in a transparent, host independent format, combined with
complete error and retry status reporting and time tagging of all messages.
The Vx/1553 driver extends the BU61580 functionality by
creating devices that may be consistently accessed whether onboard (internal-RAM) of
offboard (host-RAM) a particular BU61580. Concurrency of execution is encouraged between
the vxWorks processor building BC frames and processing RT subaddress buffers and the
BU61580 transacting messages to the bus. vxWorks devices may be attached and detached from
the BU61580, allowing a large number of virtual 1553 bus based objects. At the same time,
critical transactions occur while devices are attached, including data transfers,
minimizing copying times.
The BC driver support is built around frame devices, each
of which corresponds to a 1553 minor frame. These may be transacted to the bus on a single
cycle or autorepeat basis; the autorepeat functionality provided by the BU61580 is
generalized by the driver to permit 1 cycle, "n" cycles or indefinite activation
of BC minor frames. Frame devices may be organized on a timeline basis, or a sequential
basis. Timelineframes transmit messages at selected times within an overall fixed frame
time. Sequential frames are transmitted on an immediate sequential basis. BC frames are
initially built with detached frame devices, writing messages into vxWorks memory. After
attachment, frames may be activated to the bus, and dynamically read and written.
Ioctl operations allow attach, detach, activation,
deactivation, and wait on condition, specific message completion, or frame completion.
Special format and deformat routines, which operate on either attached or detached frames,
allow message access on an implementation independent basis.
The RT driver features both frame and subaddress devices.
Subaddress devices access the BU61580 illegalization, busy setting, and selective
condition waiting on an ioctl basis.
A mode command device allows command type waiting, data
word setting, and illegalization/busy by means of ioctl calls. Direct reads and writes to
subaddress devices support data transfer; an ioctl is available to wait on data buffering
levels. A means of reliable reading of the "most recent message" to a subaddress
is provided by the BU61580 and supported by the driver implementation.
RT frame devices allow sequential reading of incoming
messages with time tags, independent ofsubaddress and message type.
MT frame devices are similar to RT frame devices, with
additional support for message selection.
Vx/1553 software provides a device discovery interface
consistent with other Compware drivers. Hardware discovery is based in general on the
presence of the BU61580 device and self-testing specific to target devices. The BU61580
self test includes checks of RAM, register and interrupt capability. A consistent system
of defaulting allows convenient specification of functionality options at device creation
time and (with some restrictions) dynamically by means of ioctls. Help routines,
consistent vxWorks module error denotation, self check routines, and an extensive group of
test applications and scripts aid software reliability and maintainability.
Copyright (c) 1996 Compware Corp.
15-Oct-97
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