{"id":3470,"date":"2024-07-13T21:16:15","date_gmt":"2024-07-14T00:16:15","guid":{"rendered":"https:\/\/gadotti.eng.br\/?page_id=3470"},"modified":"2025-06-05T21:32:00","modified_gmt":"2025-06-06T00:32:00","slug":"lorawifimainboard","status":"publish","type":"page","link":"https:\/\/gadotti.eng.br\/index.php\/lorawifimainboard\/","title":{"rendered":"LoRaWiFiMainboard"},"content":{"rendered":"\t\t
\n\t\t\t\t
\n\t\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t\t\t\t\t

This is the first board of the TellMee IoT project, specially designed for IoT projects. It has a host controller, inputs, outputs, external memory, WiFi and LoRa modules. It can be powered by a single lithium-ion battery or connected to the mains.<\/p>

For the SW development I am using the STM32CubeIDE with C language + FreeRTOS. Internal 5 pins connector available to connect the STLink flash\/debug interface.<\/p>

The host controller interfaces via AT commands to the WiFi and LoRa modules.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

\n\t\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t

Block Diagram<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
\n\t\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t

Main Functions<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t
\n\t\t\t\t\t\t\t\t\t
  • Two possible power supplies (assembly option), both reverse polarity protected:
    Line Supply: input voltage range from 6V to 32V, with a Buck converter to 3.3V;
    Battery Supply: input voltage range from 1.8V to 5.5V, with a Buck-Boost converter to 3.3V;<\/li>
  • STM32 Arm Cortex M4 32bits, L4 family, low power uC, with 128kB Flash and 64kB SRAM (LQFP48, different uC variants are available in the family);<\/li>
  • Three Digital Inputs, configurable for High or Low active (assembly option);<\/li>
  • Two Analog Inputs, configurable for measuring positive voltage or resistance for temperature sensor (assembly option);<\/li>
  • Two Analog Inputs, configurable for measuring positive voltage or 4-20mA sensor signal (assembly option);<\/li>
  • Two Digital Outputs in open drain configuration, suitable for inductive loads, with max. current of 150mA @24V or 300mA @12V (assembly option);<\/li>
  • One channel serial line RS485, half duplex;<\/li>
  • WiFi communication, according to the standard 802.11 b\/g\/n, performed by the ESP8266-12F module. Internal PCB antenna;<\/li>
  • LoRaWAN communication, Class A, B and C according to LoRaWAN specification 1.0.3, performed by the RAK3172 module. Supported bands: IN865, EU868, AU915, US915, KR920, RU864, and AS923 (configured via SW). Ipex 1 antenna connector for external antenna;<\/li>
  • Onboard precision Temperature (+\/- 0.2\u00b0C) and Humidity (+\/- 2% RH) sensor, performed by the SHTC3 sensor;<\/li>
  • 8kbit serial EEPROM for system configuration;<\/li>
  • 8Mbit serial flash memory for data logging and firmware update process;<\/li>
  • Buzzer for acoustic warnings, typ. 2.7kHz frequency;<\/li>
  • Three LEDs for visual interface and warnings.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
    \n\t\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t

    PCB<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t

    FR4 two layers, single side SMD assembly, 90 x 60 mm<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

    \n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t
    \n\t\t\t
    <\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
    \n\t\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t

    Assembled Samples<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t

    WiFi option only and WiFi + LoRa, working as a gateway for a private LoRaP2P network<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

    \n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t
    \n\t\t\t
    <\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
    \n\t\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t
    \n\t\t\t\t\t\t\t\t\t

    The following block was not tested yet:<\/p>

    • SPI Flash Memory<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
      \n\t\t\t\t\t
      \n\t\t\t\t
      \n\t\t\t\t
      \n\t\t\t\t\t\t\t\t\t

      14\/Jul\/2024<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"

      This is the first board of the TellMee IoT project, specially designed for IoT projects. It has a host controller, inputs, outputs, external memory, WiFi and LoRa modules. It can be powered by a single lithium-ion battery or connected to the mains. For the SW development I am using the STM32CubeIDE with C language + […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"page-builder","ast-site-content-layout":"full-width-container","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"disabled","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"class_list":["post-3470","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/pages\/3470","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/comments?post=3470"}],"version-history":[{"count":79,"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/pages\/3470\/revisions"}],"predecessor-version":[{"id":3857,"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/pages\/3470\/revisions\/3857"}],"wp:attachment":[{"href":"https:\/\/gadotti.eng.br\/index.php\/wp-json\/wp\/v2\/media?parent=3470"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}