History: ip_app_mqttc

This page describes all changes made to the ip_app_mqttc package, MQTT Client, since its release.


1.47 (2021-02-08, 14:00):

  • Added support to use SCAD mapping macros (MQTT can be used with a 3rd party TCP/IP stack).
  • Added support to latest TLS module.
  • Added comments to API file.

1.46r2 (2020-02-03, 14:00):

Moved design docs to hcc/design/ip_app_mqttc.

1.46 (2020-06-17, 16:03):

  • Added missing break in receive_packets() switch statement, which could lead to user connection callback incorrectly indicating MQTTC_IP_ERROR instead of MQTRC_BUFFER_FULL error.

1.45r2 (2018-08-29, 18:28):

  • Document HTML link added to the documentation folder.
  • History and document files renamed to the package name.

1.45 (2018-03-22 22:07):

  • bugfix: subscription callback could return one more (random) character than sent by the broker.


  • bugfix: client now notifies user application about QoS2 PUBLISH packets with the same packet ID only once (exactly one delivery).


  • bugfix: client now responds to all PUBLISH packets (even if there is no subscription for it). This is a requirement of the standard.


  • Update: client is now able to receive and process multiple packets at the same time.
  • Update: indicates MQTTC_IP_ERROR whenever TCP/TLS connection is not established at connection time.


  • Update: added subscription filter to subscription callbacks so same function can be used for multiple subscriptions.


  • Update: implemented UTF-8 validator.
  • bugfix: generate multibyte remaining length field of MQTT packets with msb set.


  • Update: implemented low-level MQTT decoder/generator routines.
  • bugfix: copy QoS level of subscriptions to the packet.


  • Update: connection is retained only if CleanSession flag is cleared; internal reconnection is started only if CleanSession flag is cleared. If CleanSession flag is set, connection is wiped when the network connection is terminated.


  • bugfix: copy message length from the buffer into the packet in case of a received PUBLISH packet.


  • Initial version.