What is the D Zero?

The Datacake D Zero is a hardware for the acquisition of digital and analog signals. It offers connection for industrial sensors or 24-Volt signals of all kinds.
The recorded measurement values are transmitted via the cellular network to a corresponding cloud platform.
No programming is required for initial installation. Within a few mouse clicks, the measurement data is prepared and visualized via individual dashboards.
Thanks to on-board eSIM and a globally uniform tariff, the D Zero can be used anywhere in the world.
Thanks to its turnkey concept, it is perfectly suited for digitalisation in small and medium-sized businesses, where know-how is concentrated on the core competence of the company, but digitalisation and IoT are nevertheless hot topics.

DIN-Rail Housing

The Datacake D Zero comes as a module for the industrial DIN rail. It is therefore to be understood as a module for integrating it into your products and should therefore always be installed in an extra switch cabinet or installation housing.

Functional Description

The Datacake D Zero is based on a powerful microcontroller. This reads the connected sensors continuously and at a high sampling rate. These signals are converted into digital format by special A/D converters or driver modules. A special firmware, the so-called D Zero OS, takes care of the connection to the mobile network and the cloud in the background, reads out sensors and automatically transfers the measured data.


  • 120 MHz STM32F2 Microcontroller
  • FreeRTOS real-time operating system
  • uBlox SARA-U201 2G/UMTS cellular radio modem
  • Directly soldered embedded SIM card
  • 4 Megabyte on-board flash memory


  • 24 Volt input voltage
  • 8 digital inputs, opt. as edge counter up to 2 KHz
  • 6 analog 0-24mA inputs, for 4-20mA transmitters
  • 3 inputs for 2-wire PT100 temperature sensors
  • 2 solid state relays for up to 36V
  • 1 RS485 data interface

Digital inputs

On the D Zero there are 8 digital inputs available, which can be used for measuring or recording switching signals or counting pulses (edges). These inputs have the following characteristics:
  • Input voltage: 7 to 27 Volt
  • Frequency of the pulse counter: up to max. 2 kHz

Analog inputs

D Zero provides 6 analog inputs that can be used to measure current for industrial transmitters according to the IEC standard signal. These inputs have the following characteristics: Measuring range: 0 to 24 mA Resolution: 15 bit Internal sampling rate: 4 samples per second

RS485 interface

An RS485 interface is available for communication with intelligent sensors, a PLC or other control systems. This interface speaks the Modbus-RTU protocol and has the following features:
  • Half-duplex transceiver
  • On-board Modbus RTU driver
  • Support of different baud rates or interface configuration
  • Definition of the Modbus protocol definition via parameters in Cloud
  • Periodic polling of individual registers
  • Control of functions

The D Zero OS

  • Basic operation
  • no user intervention necessary
  • Independent connection establishment with mobile network and Datacake Cloud platform
  • Automatic query of the connected sensors
  • Transmission of the measured values according to user-defined rules
  • Saving of data volume by transmission only if there are also reasonable changes in the measured values
  • Ability to update the software via the mobile network
  • Logic through rule engine


The Datacake D Zero comes with the Datacake Cloud. On this platform you can create your own dashboards, add people for collaboration or create your own sub-areas called tenants (or as we call them: workspaces).
The Datacake Cloud, like its associated hardware (whether Datacake D Zero or Masterbrick), is designed to be used as an IoT solution for your products, machines or business models. The aim is to provide a turnkey solution that makes all the components you need available at the click of a mouse.
And so there is no need to pre-program the Datacake cloud to adapt to your products or business models. Dashboards can be created by drag and drop, users can be invited by email, and rights and other functions can be customized at the click of a mouse.

No programming required

The outstanding feature of D Zero is the parameterization of all settings via the web interface of the Datacake Cloud.
No special program in a programming language needs to be created and pre-programmed on the module for the commissioning of the D Zero. All parameters and settings can be transferred conveniently at the touch of a button without any special IT or programming knowledge. It usually takes only a few minutes from the sensor to the cloud.
Define connected sensors and their measuring range via masks. Determine how often measured values should be transmitted. Decide which measured values are particularly important. Define rules for smaller automation tasks using the editor.

The Cellular Connection

Communication with the cloud takes place via the cellular network. In addition, the D Zero is equipped with a modem that connects either via UMTS or - as a fallback - via the 2G network. On board is an embedded SIM card. It comes with a worldwide uniform tariff without roaming fees and an included data volume of 3 megabytes per month. Mobile modem, SIM card and tariff are already ready for use. Once the power supply to the D Zero is established, the modem automatically connects to the Internet and the Datacake Cloud platform.


  • UMTS cellular modem with 2G fallback (NB-IoT available).
  • Embedded SIM card with worldwide tariff (no foreign card necessary).
  • Transparent display of costs and data volume via cloud.
  • Bidirectional communication between D Zero and Cloud.
  • Regular ping between Cloud and D Zero.
  • Query of current measured values at any time.
  • Software update over the air (for importing updates, custom firmware).

Optimized transmission

In times of smartphones, 3 megabytes of data volume may seem very small. However, the transmission of the measured values is optimized in that only a few bytes of information need to be transmitted per measured value. And this includes encryption of the data.
A data volume of 3 megabytes per month is therefore usually sufficient for the entire month. Intelligent functions such as hysteresis also help to make ideal use of the data volume.

What happens if I have used the data volume of 3 megabytes per month completely?

No worries. The intelligent functions of the firmware prevent this in most cases. If the data volume of 3 megabyte per month is not sufficient, each additional megabyte used will be charged with 1.40€.

Why do I use up my data volume too quickly?

Reasons for this are usually wrong settings or a requirement that requires measured values to be transmitted with a high interval.

Encryption and security

While still on D Zero, the data to be transmitted is encrypted using the DTLS protocol. For this purpose, the firmware uses a special key that only the cloud knows. The key is used to decrypt the data received from the cloud. During transmission, the data is completely encrypted.
We use the most modern procedures here, which are constantly controlled and extended. In addition, the keys for logging on to the Datacake cloud platform or for encrypting the data are regularly exchanged.