The MIL-STD-1553 data bus delivers connectivity and communication for military and commercial equipment. Like the relationship between the personal computer and local area network (LAN), the data bus system provides the medium for the exchange of data and information between various avionic systems.
Shrinking budgets have forced many suppliers to focus on costs in an effort to meet the military and commercial demand. While cost is important to suppliers that build these systems, there are other differentiators that benefit the customer. Like the LAN, there are manufacturers of electronic interface hardware that produce supporting software products with the richest set of features.
Hardware and Software Capabilities
Avionics hardware modules and software are targeted to interface with a wide-range of applications. In particular, Avionics systems support the application of design, verification and integration. They also provide aircraft maintenance and test applications along with manufacturing and production. With airborne or on board aircraft, avionics applications are crucial to the network switch application for Ethernet and fiber channel. These products are manufactured for and available to both the military and commercial sectors.
Little Black Box
The hardware elements include the remote terminals, bus controller and bus monitor in addition to the terminal hardware. The primary purpose of the data bus is to move data between black boxes. The features behind the 1553 data bus include a data rate of 1 MHz, 20 bits word length with a maximum 32 data words in total message length. The transmission technique is half-duplex, and the operation is asynchronous. The protocol is a command/response to single or multiple bus controls. There are multiple message formats including:
- Controller to Terminal
- Terminal to Controller
- Terminal to Terminal
- Broadcast
- System Control
The maximum number of remote terminals is 31, and the transmission media is twisted shielded pairs with coupling for both transformer and direct.
First Things First
When it’s time to issue a request for information, consider targeting a supplier that is a leading designer and manufacturer of electronic interface hardware. Also, be sure the supplier provides supporting software products for your Avionics data buses. It is advisable to work with a supplier that not only works within cost constraints but produces avionics with expertise and focuses on delivering high-quality features.