From 582b655b45986ee775bc3a77d95fae0e63e162e3 Mon Sep 17 00:00:00 2001 From: Steven Christe Date: Thu, 10 Oct 2024 13:18:31 -0400 Subject: [PATCH] fixes to link to bluebook and update to sequence control field --- README.rst | 2 +- docs/user-guide/ccsds.rst | 14 +++++++------- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/README.rst b/README.rst index 14e156a..fb569a7 100644 --- a/README.rst +++ b/README.rst @@ -15,7 +15,7 @@ CCSDSPy - IO Interface for Reading CCSDS Data in Python. :target: https://doi.org/10.5281/zenodo.7819991 :alt: Zenodo DOI -This community-developed package provides a Python interface for reading tightly packed bits in the `Consultative Committee for Space Data Systems (CCSDS) `__ format used by many NASA and ESA missions. The library is developed with requirements sourced from the community and extensive automated testing. +This community-developed package provides a Python interface for reading tightly packed bits in the `Consultative Committee for Space Data Systems (CCSDS) `__ format used by many NASA and ESA missions. The library is developed with requirements sourced from the community and extensive automated testing. Used By ------- diff --git a/docs/user-guide/ccsds.rst b/docs/user-guide/ccsds.rst index 7b38a5c..a150e3a 100644 --- a/docs/user-guide/ccsds.rst +++ b/docs/user-guide/ccsds.rst @@ -6,9 +6,9 @@ CCSDS Overview ======== -The `Consultative Committee for Space Data Systems (CCSDS) `__ is a multi-national forum for the development of communications & data systems standards for spaceflight. -It maintains space communications & data handling `standards `__ to enhance interoperability across governmental & commercial projects. -One of the standards published by this group is the `CCSDS Space Packet protocol `__ which defines how space missions transfer space application data both sending and receiving. +The `Consultative Committee for Space Data Systems (CCSDS) `__ is a multi-national forum for the development of communications & data systems standards for spaceflight. +It maintains space communications & data handling `standards `__ to enhance interoperability across governmental & commercial projects. +One of the standards published by this group is the `CCSDS Space Packet protocol `__ which defines how space missions transfer space application data both sending and receiving. The maximum length of a CCSDS packet is 65536 A CCSDS packet is made of three parts: a required primary header, an optional secondary header, and a User data section. @@ -66,12 +66,12 @@ The mandatory packet primary header consists of four fields contained within 6 o * - Application process identifier or APID - 11 - The APID provides a way to uniquely identify sending or receiving applications on a space vehicle. - * - Packet sequence control field - - + * - Packet sequence control field or packet name - + - For telemetry packets, the sequence field shall contain the Packet Sequence Count. For command packets, this field shall contain either the Packet Sequence Count or 14-bit Packet Name. * - Sequence flag - 2 - - Set to '01' if the data is a continuation segment, set to '00' if it contains the first segment of data. + - Set to '11' if unsegment data, set to '01' if the data is a continuation segment, set to '00' if it contains the first segment, '10' if the last segment. * - Packet sequence count or packet name - 14 - the sequential binary count of each packet for a specific APID. The purpose is to allow packets to be ordered. @@ -79,4 +79,4 @@ The mandatory packet primary header consists of four fields contained within 6 o - 16 - The length in octets of the remainder of the packet minus 1 octet. -For more information see Section 4.1.3 of the `CCSDS Blue book `_. +For more information see Section 4.1.3 of the `CCSDS Blue book `_.