The rising popularity and proliferation of I2C device demands specialized measuring equipment for analysis. The article will be looking into accelerating R&D by using Logic Analyzers for analyzing I2C protocols, and, coupled with AAEON’s proprietary Hi-Safe Software, checking the read/write operation of I2C devices.
An Introduction to the I2C Protocol
Data transfer with the I2C protocol begins with a START condition(s), followed by a slave address (7-bits long), a data direction bit (R/W#), Acknowledgement (ACK), and concludes at STOP (P).
An introduction to AD5247
The AD5247 is a 128-position I2C Digital Potentiometer by Analog Devices and serves as an IC to control the brightness of a LCD in AAEON designs. Its 128-position characteristic and convenience brought on by I2C control makes it very viable for this application.
GUI of AAEON’s Hi-Safe Software
With a Logic Analyzer acting as an I2C protocol analyzer and Bus decoder, engineers will get the first hand information on the data’s read/write status, an impossible feat when oscilloscopes is used for measuring such data-rich information. In Hi-Safe, switching to slave address 2E of AD5247, and setting 00 to both Register of data and Byte 0 will reveal the waveform of WRITE 00, as shown below.
When data is set to 1A, the waveform of WRITE 1A is revealed, as shown below.
Data byte), ACK, Stop cycle are highlighted in different colors to make them quicker to be identified and easier to read.
From the image, the changes in S (start), Frame 1 (Slave address byte), ACK, Frame 2 (Register of data), ACK, Frame 3 (Data byte), ACK, Stop cycle are highlighted in different colors to make them quicker to be identified and easier to read.
Meanwhile, the operational status of I2C cycle can be determined by measuring the voltage variations at the output of the AD5247.
By using the convenient Hi-Safe, the accuracy of the software engineer’s code to the hardware’s circuitry can be determined immediately, greatly minimizing the debugging time needed during development. Not only that, the status of each functions can be known with more precision when a hardware revision is due, shortening the time to market.
AAEON BIO Interface:
Three Ways How Customization Just Got Simpler
For providers/manufacturers of solutions, the ability to cater their products to the specific requirements of each and every application, and doing it timely and resourcefully, becomes part of their bread and butter.
Many of these companies attempt to accomplish this through customization, which can turn into a tedious and time-consuming process without the correct foundation. However, even if clear requirements are laid out, the process may very often involve stripping the original offering down to its individual components and reassembling it to its required specification. Lengthy testing and monitoring are ensued to ensure a complete, fault-free delivery.
With years of experience in customization and full acknowledgement of the labor and time involved, AAEON has come up with a proprietary interface that may achieve the same purpose with minimum resources, and this White Paper will shed more light into this new hardware.
Referred to as the BIO interface (not to be confused with BIOS), which stands for board-to-board I/O connector, this 80-pin connector incorporates a variety of commonly used signals such as USB 2.0/3.0, DDI, Audio, and GPIO and works just like a PCI or any other expansion slots. This allows users to implement their desired features without having to invest heavily towards R&D.
When users need more from the base (mother) board, simply select the features that are additionally needed for a daughter board, connect the new board with the original board via the BIO interface and everything is set to go, no fuss, no muss.
The appearance of the daughter board may lead to questions about its unconventional shapes. And also how this oddly shaped card and this small interface is going to help with building the ideal system. These questions will be answered in the sections below.
As mentioned previously, it is important for the customization to be carried out in the most time and resource-conscious manner to reduce cost to the provider/ manufacturer. The BIO interface is the brainchild of that idea, serving to eliminate the unnecessary resources into bringing a customized product up to speed through various designs.
The first of which is the physical size of the connector and the daughterboard; the former measures 44 mm in length, 20 mm in height while the latter features different board shapes to ensure compactness. The distinctive shapes are purposefully designed for maximizing space otherwise impossible for conventional rectangular boards, as at least 2 boards can be fitted within the same area.
Second is the adoption of a cableless design. By excluding cables, the board looks much neater and makes maintenance easier. Also, as the boards are not connected with wires, it brings about another advantage which will be discussed next.
With the BIO interface, stability is assured in two aspects, physical and functional. The former is catered for with a sturdy connector that offers better protection against motions and vibrations than wired connections; the latter through standardized hardware, as products designed to carry the interface use the same hardware and signals for communications, completely stamping out any conflicts.
In addition, all BIO interface-equipped products are tested on the same platform as the customer’s to make sure it is bug-free before shipping.