You need to test, we're here to help.

You need to test, we're here to help.

18 May 2018

Examples of IoT DDR Debug Scenarios

Using the oscilloscope's Track math function can help pin down timing anomalies
Figure 1: Using the oscilloscope's Track
math function can help pin down
timing anomalies
Our last post considered some broad aspects of debugging DDR memory on Internet of Things (IoT) devices, such as how chip interposers can help with probing access and the benefits of virtual probing software. Let's now take a look at some particular examples of problems with these memory chips and their controllers and see how debugging with an oscilloscope might be approached.

15 May 2018

Debugging DDR Memory on IoT Devices

Embedded systems such as IoT devices often require chip interposers to gain access to signal lines on DDR memory
Figure 1: Embedded systems such as IoT devices often require
chip interposers to gain access to signal lines on DDR memory
Internet of Things (IoT) devices are, at heart, just another embedded computing system, albeit one with an extremely well-defined function. As such, there's bound to be some amount of on-board data storage, and the storage medium of choice these days is typically double data-rate (DDR) memory. DDR memory transfers serial data on both the rising and falling edges of the clock signal, which is the characteristic from which it derives its name.

10 May 2018

Debugging Ethernet, SATA, and PCIe for IoT Devices

A generic IoT block diagram shows serial-data links in blue
Figure 1: A generic IoT block diagram
shows serial-data links in blue
In our ongoing review of debugging serial-data standards for Internet of Things (IoT) devices, let's now turn to three more popular protocols: Ethernet, SATA, and PCIe. Ethernet is found in computer networking applications, while the Serial Advanced Technology Attachment (SATA) connects host bus adapters to mass-storage devices. The Peripheral Component Interconnect Express (PCI Express or PCIe) handles communication between root complexes (motherboards) and expansion-card interfaces.

08 May 2018

Debugging CANbus For IoT Devices

Temperature data from thermocouples is shown both encoded and decoded on the oscilloscope's display
Figure 1: Temperature data from
thermocouples is shown both
encoded and decoded on the
oscilloscope's display
A myriad of serial-data standards come into play when we're discussing Internet of Things (IoT) devices. We've talked about I2C, SPI, and UART in a previous post. Yet another serial-bus standard that comes under the IoT umbrella is the Controller Area Network (or CANbus) standard. CANbus enables microcontrollers and peripheral devices to communicate with each other in applications without an intervening host computer. In the past, it's been typically used in automotive applications, but CANbus has found its way into a wider scope of applications of late.

04 May 2018

Debugging Low-Speed Serial Data on IoT Devices

Serial-data links handle traffic between ICs and peripheral devices in the IoT world
Figure 1: Serial-data links handle traffic between ICs
and peripheral devices in the IoT world
Our last post discussed the difficulties in acquiring the many sensor signals that may be input to a deeply embedded system such as an IoT device as well as a hardware solution to the problem. Another aspect of IoT debugging and validation is the low-speed serial data standards used to facilitate communication between ICs and between controllers and peripheral devices (Figure 1). To that end, let's take a look at three such low-speed standards: I2C, SPI, and UART.

02 May 2018

Acquiring and Characterizing IoT Sensor Signals

IoT devices use many sensors to collect data about their ambient environment
Figure 1: IoT devices use many sensors to collect data
about their ambient environment
If we recall our earlier post with its definition of what constitutes an Internet-of-Things (IoT) device, one of the main functions of such devices is to sense its environment and digitize the collected data. Often, an IoT device uses many sensors to collect information about its environment (Figure 1). Having the ability to capture and analyze signals from numerous sensors simultaneously is critical to ensure proper and optimal functionality of the IoT device's design.

30 April 2018

Investigating IoT Wireless Signals (Part II)

This screen capture depicts frequency demodulation and subsequent Manchester decoding of the bit stream
Figure 1: This screen capture depicts frequency demodulation
and subsequent Manchester decoding of the bit stream
Internet of Things (IoT) devices must communicate with their peers--other IoT devices--as well as with the host system that governs their activities. In our previous post, we examined how to perform amplitude and frequency demodulation of RF bursts, such as Bluetooth Low Energy (BLE) advertising bursts. We'll continue with other methods of analyzing RF signals.