I.B. + M.A. DE LANDE LONG
SOFTWARE + CONSULTANCY

Telemetry Encoder Shell package: Detailed description

Software Interfaces

The Telemetry Encoder Shell is a software package, designed to be built into a software system for a telemetry application. The part of the software system which lies outside the Shell is called the Telemetry Encoder Environment. The API (Application Programming Interface) consists of function calls between the Environment and the Telemetry Encoder Shell.

The Telemetry Encoder Shell accepts telemetry data formatted as packets. It also accepts data for the Frame Secondary Header (FSH) and the Operational Control Field (OCF). The Operational Control Field can be used to carry CLCWs (Communications Link Control Words) for packet telecommand. See the separate description for details of this and other Packet Telemetry Features supported by the Telemetry Encoder Shell.

The Telemetry Encoder Shell delivers transfer frames, ready for coding and modulation.

The Environment calls the Shell to:

pass packets to the Shell
pass data for the OCF and FSH to the Shell
time the delivery of the next frame.

The Shell calls the Environment to:

provide responses to packet requests
deliver telemetry transfer frames to the Environment.

Telemetry Encoder Shell software i/f

There are management interfaces in the API. The Environment needs to call the Shell to:

initialise and configure the Shell
pass control of the CPU to the Shell (scheduling)
get optional status reports
terminate the Shell.

The management interfaces from the Shell to the Environment include calls to the Environment for storage allocation and for the optional logging of messages.

Telemetry Encoder Shell package

The Telecommand Encoder Shell package consists of:

a set of C header files defining the interfaces
a sample user program to demonstrate use of the Shell, including examples of all the Environment functions which are called by the Shell
a library of modules implementing the Telemetry Encoder Shell
the Telemetry Encoder Shell Software User Manual.

A telemetry system built with this package is likely to be very much cheaper than independent development of an equivalent capability.

Licensing and support may be negotiated according to requirements. All the Packet Telemetry features are included in the Telemetry Encoder Shell.

The Telemetry Encoder Shell code is written in ANSI/ISO 9899-1990 C and is highly modular and easy to maintain. The code makes no calls to the operating system run-time libraries and it is therefore easily portable to different computer architectures. The code has been compiled by a number of independent ANSI C compilers and the demonstration program produces identical results in each case.

Please contact us for further information on technical questions or licensing conditions for the Telemetry Encoder Shell package.

Portability TM Features TM Encoder Shell TM Decoder Shell