The Dash v1.2 is a fully open source reference design and prototyping platform for developers to rapidly test and move applications to market. The Dash helps developers makes connectivity simple and enables embedded applications to interface with other peripherals and sensors through an array of GPIO, serial interfaces, and analog pins. The on-board microcontrollers and battery management ICs make the Dash are ideal for low-power, low data usage applications.
The Dash uses two microcontrollers:
The System microcontroller is Freescale's MKL17Z256VFM4 which features a 32-bit ARM Cortex-M0+ that runs at 48 MHz and has 256 kB Flash and 32 kB RAM. This microcontroller manages the u-blox modem as well as connections into Hologram's cloud.
The User microcontroller is Freescale's MK22FN1M0AVLH12 which features a 32-bit ARM Cortex-M4 that runs at 120MHz and has 1MB Flash and 256kB RAM. This microcontroller exclusively hosts user programs that are fully compatible with Arduino APIs. (Note: although our firmware is fully Arduino-compatible, when loading Arduino libraries on the Dash, it is important to check the library for hardware-specific calls. In these cases these libraries will not be compatible with the Dash out of the box.)
Hologram is committed to providing open source hardware to enable developers looking for a field-tested and readily scalable reference design.
The Dash v1.2 is certified by the OSHWA (Open Source Hardware Association) under identifier US000082. The design can be modified and adapted to any application (commercial or otherwise).
The Dash v1.2 can be powered using the USB5V, VBATT, or SystemVin pins. The Dash v1.2 can power other peripherals through the VSystemUser and 3.3V pins. Allowable minimum and maximum voltage and current for these power inputs and power outputs is listed below.
*System_User is a reference to the internal 5V power supply, protected by an input diode.
** Current draw by peripherals on this pin should be limited to 250mA to maintain normal operation of internal Dash components.
Peripherals and GPIO on the Dash v1.2 minimum and maximum voltages are listed below. The Dash user microcontroller works at 3.3V (i.e. 3.3V registers as a “1” for digital GPIO and analog input) and the digital pins are 5V tolerant whereas the analog pins are 4.1V tolerant.
*Denotes single SPI with 2 configurations
The Dash has three different power operating modes that are configurable via API:
Battery charging is automatically managed by the MCP73871-2CCI/ML IC.
The details for the MCP73871-2CCI/ML can be found on the datasheet.
The Dash v1.2 features the global band SARA-U201 or the global band SARA-R410M depending on 3G/2G or Cat-M/NB-IoT variant, respectively. Both of these modems are considered global band and work anywhere we have 2G/3G or Cat-M1 coverage, respectively.
The SARA-U201 modem supports a global list of 2G and 3G frequencies:
The SARA-R410M modem supports a global list of Cat-M1 and NB-IoT bands:
These bands correspond to Uplink and Downlink frequencies in the following ranges (in MHz):
The full list of bands and frequencies can be found in the u-blox SARA datasheet.
The Dash includes 3 different LEDS and two different buttons:
Reset Button: Resets the user microcontroller.
Program Button: used to put Dash into programming mode.
Program LED: flashes when the Dash is in programming mode
User LED: full configurable by user programs using the Arduino IDE
RGB LED: configurable by user programs
Read more about configuring both User and RGB LEDs in our Dash API reference.
The Dash is made for ultimate flexibility and this extends to the antenna. The stock black antenna has the following characteristics:
The Dash v1.2 can be ordered in small quantities (i.e. our store.
For higher volume orders, please contact sales for a quote.