clarified the "RESET" commands, simplified the command list a bit (ch…

…anges

to configurations should be performed via changes to the tables), and added
a requirements document.

doc/Requirements.md

@@ -0,0 +1,200 @@
+---
+title: Core Flight Software - Software Bus Networking Requirements
+tags: cFE SBN
+abstract: Software Requirements for the Core Flight System Software Bus
+          Networking (SBN) application
+---
+
+# Software Bus Networking Requirements (cFE SBN) {#SBN}
+
+## SBN: Application Requirements {#SBN10}
+
+### SBN1000
+
+SBN shall be a Core Flight Software application and comply with cFS
+application interface requirements.
+
+### SBN1001
+
+SBN shall provide one or more network modules, each of which shall interface
+with a network technology over which SBN shall transmit and receive messages
+from configured SBN peers.
+
+### SBN1001.1
+
+SBN shall support zero or more networks, up to a configured maximum number of
+networks. Each network may use any one of the network modules and SBN
+shall allow multiple networks, each utilizing a different network module.
+
+### SBN1001.2
+
+For each configured network, SBN shall communicate with zero or more peers,
+up to a configured maximum number of peers per network, per the compile-time
+limit.
+
+### SBN1002
+
+SBN shall automatically establish and maintain connections to peers.
+
+*Rationale: Networks may be unreliable or otherwise experience radiation-
+induced errors that may interrupt the connection.*
+
+### SBN1003
+
+SBN shall continue to relay messages to connected peers even when some
+peers in the network are not connected.
+
+*Rationale: Networks may be unreliable, or peers may be brought online or
+offline separately from this cFS instance.*
+
+### SBN1004
+
+SBN shall use a minimum of network and processor resources.
+
+*Rationale: Resources are limited and valuable.*
+
+### SBN1004.1
+
+SBN shall interface with cFS to track all subscriptions made by local
+applications and shall communicate those subscriptions to all peers.
+
+*Rationale: Communicating the subscription information ensures that only
+messages relevant to local applications are received and only messages
+relevant to remote applications are sent.*
+
+### SBN1004.2
+
+SBN shall only send messages for peer connection awareness when required
+for the network technology.
+
+*Rationale: Some network technologies lack an infrastructure to track
+whether a connection is currently/still established. In order to communicate
+subscription state information, SBN needs to be aware of the state of
+connections so that if a peer connection is lost and re-established,
+all local subscriptions must be retransmitted. However, network resources
+are limited, so only the minimum amount of traffic shall be sent to
+maintain awareness.*
+
+### SBN1004.3
+
+When configured to do so, SBN shall filter out messages with particular
+identifiers that would normally be sent to a peer.
+
+*Rationale: By default, SBN will send all subscribed-to messages to a peer.
+There may be some configurations where this would result in a great deal of
+unwanted traffic.*
+
+### SBN1005
+
+When configured to do so, SBN shall translate local message identifiers
+prior to sending to a peer. This translation shall be configurable per peer.
+
+*Rationale: Complex spacecraft configurations may involve multiple subsystems
+managed by different organizations and may have complex configuration
+management. Translations will reduce the impact of subsystem changes.*
+
+### SBN1006
+
+All SBN headers shall be in network-byte (big-endian) order.
+
+*Rationale: SBN may be used in an environment where some peers are of a
+different byte order.*
+
+### SBN1007
+
+All SBN-generated protocol messages shall be in network-byte (big-endian) order.
+
+*Rationale: SBN may be used in an environment where some peers are of a
+different byte order.*
+
+### SBN1008
+
+SBN shall not modify messages it receives from peers and shall inject those
+messages onto the local Software Bus.
+
+*Rationale: Until EDS is implemented in cFS, understanding the complexity
+of the message structures for every message would be burdensome and, once
+EDS is implemented, would become redundant.*
+
+### SBN1009
+
+SBN shall not modify Software Bus messages it sends to peers.
+
+*Rationale: Until EDS is implemented in cFS, understanding the complexity
+of the message structures for every message would be burdensome and, once
+EDS is implemented, would become redundant.*
+
+### SBN1010
+
+SBN shall track housekeeping information and, when commanded to do so,
+transmit that information as housekeeping messages on the local Software
+Bus (to be downlinked by other cFS components.)
+
+Housekeeping statistics to be tracked:
+
+- Valid commands received by this application.
+- Invalid commands received by this application.
+- Per-peer, the number of messages sent to a particular peer.
+- Per-peer, the number of messages received from a particular peer.
+
+## SBN: Operational Interface {#SBN20}
+
+### SBN2000
+
+SBN shall be configured by a cFS-standard compile-time configuration
+header file, defining relevant upper and lower limits and other sizing
+parameters.
+
+### SBN2001
+
+SBN network configuration shall be described in standard cFS Tables.
+
+### SBN2002
+
+SBN remapping/filtering configuration shall be described in standard cFS Tables.
+
+### SBN2003
+
+SBN shall comply with Core Flight Software application interface requirements.
+
+### SBN2004
+
+Upon receipt of a Command, SBN application shall generate a NO-OP event message.
+
+*Rationale: This command is useful as a general sub-system aliveness test.*
+
+### SBN2005
+
+Upon receipt of a valid Command, SBN shall increment a valid Command 
+counter.
+
+*Rationale: The ground needs the capability to verify that the command was
+received and accepted by SBN.*
+
+### SBN2006
+
+Upon receipt of an invalid Command, SBN shall increment the invalid Command 
+counter and generate an event message.
+
+*Rationale: The ground needs an indicator if a command is rejected by SBN.*
+
+### SBN2007
+
+Upon receipt of a Command, SBN shall send housekeeping telemetry indicating
+the operating status of the application.
+
+*Rationale: The ground needs an indicator of the current running state of SBN.*
+
+### SBN2008
+
+Upon receipt of a Command, SBN shall send housekeeping telemetry indicating
+the current operating status regarding a particular peer.
+
+*Rationale: The ground needs an indicator of the current running state of SBN.*
+
+### SBN2009
+
+Upon receipt of a Command, SBN shall set to zero the housekeeping statistics.
+
+*Rationale: This command is a common feature in heritage sub-system software
+design.*

fsw/platform_inc/sbn_interfaces.h

@@ -281,20 +281,6 @@ struct SBN_IfOps_s {
      */
     int (*ReportModuleStatus)(SBN_ModuleStatusPacket_t *Buffer);
 
-    /**
-     * Resets a specific peer.
-     * This function must be present, but can simply return SBN_NOT_IMPLEMENTED
-     * if it is not used by or not applicable to a module.
-     *
-     * @param Peer[in] Peer to reset
-     *
-     * @return  SBN_SUCCESS when the peer is reset correctly.
-     *          SBN_ERROR if the peer cannot be reset.
-     *          SBN_NOT_IMPLEMENTED if the module does not implement this
-     *          function.
-     */
-    int (*ResetPeer)(SBN_PeerInterface_t *Peer);
-
     /**
      * Unload a network. This will unload all associated peers as well.
      *

fsw/platform_inc/sbn_msgdefs.h

@@ -2,18 +2,14 @@
 #define _sbn_msgdefs_h_
 
 #define SBN_NOOP_CC             0
-#define SBN_RESET_CC            1
-#define SBN_RESET_PEER_CC       2
-
-#define SBN_REMAPCFG_CC         5
-#define SBN_REMAPADD_CC         6
-#define SBN_REMAPDEL_CC         7
 
 #define SBN_HK_CC               10
 #define SBN_HK_NET_CC           11
 #define SBN_HK_PEER_CC          12
 #define SBN_HK_PEERSUBS_CC      13
 #define SBN_HK_MYSUBS_CC        14
+#define SBN_HK_RESET_CC         15
+#define SBN_HK_RESET_PEER_CC    16
 
 #define SBN_SCH_WAKEUP_CC       100
 #define SBN_TBL_CC              110