Skip to content

Latest commit

 

History

History
65 lines (48 loc) · 3.1 KB

File metadata and controls

65 lines (48 loc) · 3.1 KB

Modbus RTU Sensor Hub

Releases License


🚨 This project is not yet in V1.0 state and is to be considered a work in progress. A release will be created when everything is working as expected.


This PCB with limited footprint is designed to provide a robust and versitale sensor hub using Modbus RTU over RS485.

PCB

General

PCB measurements: ca 32mm x 30.5mm x 11mm

PCB Front PCB Back
PCB Front PCB Back

Microcontroller

The sensor hub leverages the very capable ATtiny3216 (arduino compatible!).

  • 32Kb flash, 2k SRAM - that's the same as an ATmega328p!
  • 17 available I/O pins
  • 8 PWM pins (6 on TCA0, 2 on TCD0) with 8-bit resolution.
  • Servo, Tone, Serial, SPI and Wire (I2C) support "just works"
  • 2 Type B timers - so Servo and Tone can both be used simultaneously, or one or both can be taken over for input capture, periodic interrupt, or other functionality.
  • DAC output (just do analogWrite() on the DAC pin - voltage is between 0V and the DAC reference voltage, which can be set with setDACReference() ).
  • 11 analog inputs, referenced to Vcc, external reference, or one of the 5 built-in analog references. Internal clock at up to 20MHz at 5v, up to 10MHz at 3.3v

Microcontroller Pinout

Capabilities

  • wide range of allowed power supply voltage: 7-30V
  • onboard convertor for 3.3V power supply (300mA max)
  • onboard convertor for 5V power supply (1.5A max, board power consumption not included)
  • two dedicated RS485 connector for leveraging Modbus RTU (bus in and out)
  • dedicated 1-Wire connector
  • dedicated UPDI connector for programming the board
  • dedicated SPI connector
  • dedicated I²C connector
  • 2 remaining digital pins
  • 4 remaining digital/analog pins

FeatherDiagram

Getting started

Example projects