Category 11 LTE Supported on Full Mini PCIe Card

Telit has announced the LM940, a global Full PCI Express Mini Card (mPCIe) module for supporting LTE Advanced Category 11 (Cat 11) with speeds of up to 600 Mbps, available with various mobile network operator approvals in the fourth quarter of 2017. According to Telit it is the only enabling technology in an mPCIe form factor to support Cat 11 with the Snapdragon X12 LTE modem. The card gives system designers additional bandwidth and near instant network response times to serve applications like high definition video streaming for digital signage. The Snapdragon X12 LTE modem with LTE Advanced Telit urltechnologies provides peak download speeds of 600 Mbps.

The LM940 iallows OEMs to immediately leverage the 3x carrier aggregation and the higher order modulation of the 256 QAM capabilities currently available amongst most mobile operator networks. Combined with an exceptional power efficiency platform, the card is well suited to enable commercial and enterprise applications in the router industry, such as branch office connectivity, LTE failover, digital signage, kiosks, pop-up stores, vehicle routers, construction sites and more.

Telit | www.telit.com

G-Code CNC Router Controller

Brian Millier constructed a microcontroller-based, G-code controller for a CNC router. So, we gave the retired instrumentation engineer space to publish a two-part series about his project.

In Part 1 (Millier-CC-2013-04-Issue 273), Millier explains the basics of G-code and how it is converted into three-axis motion, via the router’s three stepper motors. In Part 2, he describes his design of the router’s axis controller (powered by three small microcontrollers) and the host controller (powered by a more powerful microcontroller).

He calls the project one of the most challenging he has ever tackled.

So why bother? Especially when the combination of a PC and ArtSoft’s Mach3 software is a common and affordable approach to running a CNC router? Well, like most DIYers, Millier couldn’t resist an opportunity to learn.

“I want to be upfront and say that this is probably not the most practical project I have ever done,” Millier says in Part 1. “You can usually pick up a used PC for free, and the Mach3 software is professional-grade and handles much more complex G-code programs than my DIY controller will. However, it did provide me with a challenging programming task, and I learned a lot about designing a program with many concurrent tasks, all of which are quite time critical. Even if you are not interested in building such a controller, you may find interesting some of the techniques and tricks I used to provide the multi-axis stepper-motor motion.”

Millier’s two articles focus on the two main tasks of his project.

“The first was to understand the G-code language used to program CNC machines well enough to be able to write the firmware that would parse the G-code commands into something that a microcontroller could use to control the stepper motors used for each of the three axes,” he says. “The second task was to design the hardware/firmware that would actually control the three stepper motors, all of which had to move synchronously at accurate, ramped speeds.”

Millier wraps up his project by saying: “This was probably the most challenging project I’ve tackled, outside of work projects, in many years. In particular, the Basic program code for both of the controllers ran beyond 3,500 lines.”

You can Millier-CC-2013-04-Issue 273. The second article is available via Circuit Cellar’s webshop.