This practical guide gives us an opportunity to take a relaxed approach to getting started with the TS-7670 single board computer. We’re going to take a look at how to make our first connections, and setup the network. These are usually the first things we do before starting development. In the grand scheme of things, this is just a friendlier extrapolation from the official TS-7670 manual, so be sure to keep it handy for more advanced topics and specific details. The only assumption being made is that you’ve purchased the TS-7670 with a development kit, including the pre-programmed microSD card. Right then, let’s get started!
One big draw to the TS-7670 is the GPS receiver feature. When paired with a wireless network, such as through WiFi or cellular, it becomes a powerful tool in asset tracking or geo surveying. In this quick guide, we’re going to go through what it takes to get GPS working and how to read the data.
Print Your Own Baseplate for Development and Prototyping
A new development baseplate and accessories for the TS-7670, TS-7680, and TS-7970 are now available for 3D printing. The main baseplate features standoffs for securing the single board computer (SBC), clip mounts for cable management, and tabs for attaching accessory boards. The accessory boards include a full sized breadboard mounting plate, and two (vertical and horizontal) half-sized breadboard mounting plates with compartments for organizing resistors and components. Two different sized cable clips are also included. You can download the STL files for 3D printing by referring to the product webpage in the resources tab, or directly here:
Let’s take a quick look at what it takes to read from the ADC inputs of a i.MX28 based embedded system using example C code provided by Technologic Systems. Now, while this can be generically applied to many i.MX28 based embedded systems, we’ll be working with a TS-7680. Right, let’s get started!
Here’s an example program our engineers might find useful. Kris Bahnsen, a long time engineer for Technologic Systems, wrote this simple program to get the voltage input (Vin) on the 8 – 28 VDC power rail on the TS-7670 (Rev. D or later) or TS-7400-V2 (Rev. B or later). Without going into too much detail about implementation of the on-board supervisory microcontroller, there is a register which is used to store various ADC values, including Vin. This example program basically polls this 4 byte register via I2C interface, accounts for the voltage divider (see TS-7670 schematic or TS-7400-V2 schematic), and spits out the Vin value. So, without further ado, here’s the code:
Having access to live data from out in the field is incredibly valuable in making smart, informed decisions about your business. Fleet vehicle and other traveling asset operations benefit greatly from an in-vehicle data logging and tracking solution. The challenge is collecting and sharing this data reliably because of the inherent challenges with a mobile solution. For example, there are additional power supply considerations for a vehicle that is always starting and stopping. When power is unexpectedly cut off from the embedded data logger, there is a high likelihood of filesystem and data corruption. Another consideration is how to transfer the data once you’ve captured it via CAN or GPS. Thankfully, cellular network providers have done a great job at providing an always-available, nationwide service accessible from nearly anywhere. It would make sense to tap into this network using a cellular modem. Then, perhaps when the vehicle returns to a base station, WiFi or Bluetooth connections can be used to share auxiliary, non-real time data. Lastly, you’ll want to consider operating temperature ranges, as the inside a vehicle can easily reach 130 ºF to 170 ºF (54 ºC to 76 ºC) and on the opposite, reach “Ice Road Truckers” cold to -50 ºF (-45 ºC). It’s important to keep these considerations of power, temperature, and connectivity in mind in order to keep all this data safe and sound. The TS-7670 and TS-7680 single board computers are embedded systems which aim to provide reliable, low power, industrial-grade vehicle asset tracking solutions and solve these challenges.