Application and Design Trends of Brand New 32bit MCUs for Embedded Connectivity
Sponsored content [Friday 21 February 2014]
Addressing the embedded market's demand for high-performance, energy-saving and connected systems, Microchip has developed solutions basing on the MIPS32 microAptiv core architecture, offering support for high computing power per megahertz, large memory capacity and a wide variety of peripherals. The integrated development framework that combines versatile in-house or third-party drivers, libraries, real-time operating systems and middleware components substantially shortens the time for development and verification of 32bit MCU program codes.
The PIC32MZ EC family
Microchip's PIC32MZ Embedded Connectivity (EC) family consists of 32bit microcontrollers developed for embedded applications with Internet connectivity. "PIC32MZ is a breakthrough that features large memory capacity and integrated peripherals. It provides class-leading performance such as 330 DMIPS and 3.28 CoreMarks/MHz at 200MHz, enabling more than three times the performance of the previous-generation PIC32MX MCUs, and downsizing storage space/density of program codes by 30% compared with competitors' 32bit MCUs," said CY Lin, technical manager at Microchip. "Boasting industry-leading designs, PIC32MZ incorporates the 12bit analog-to-digital converter (ADC) with a sampling rate of 28M per second, much faster than ordinary MCUs whose ADCs offer maximum sampling rates no higher than a few MHz. PIC32MZ can be relied on to create applications that have been previously beyond imagination."
PIC32MZ's remarkable features include: maximum 2MB flash and 512KB SRAM; dual-panel flash with Live Update that allows original firmware burning to be continued in a different flash memory block of a running MCU to which the upgraded firmware is simultaneously downloaded; and SRAM capacity which is four times as large as that of the previous-generation MX family.
"PIC32MZ integrates peripherals such as Hi-Speed USB 2.0, 10/100Mbps Ethernet controller, two CAN 2.0b control modules, six UARTs, six SPI/I2S serial interfaces, five I2C communications interfaces, and 4bit Serial Quad Interface (SQI)," Lin said. "PIC32MZ with the built-in hardware crypto engine encrypts data such as AES/3DES/HA, MD5 and HMAC, reinforcing safety of e-commence, such as on-line shopping."
The PIC32MZ EC family provides a series of development tools, from entry-level Starter Kits, Plug-in Modules (PIMs) to full Developer Boards. A Starter Kit costs about US$119, and a PIM US$25. A Starter Kit with Multimedia Expansion Board II allows peripherals to directly plugged-in to form embedded system prototypes. And a 168-pin to 132-pin adapter board costs US$59.
The PIC32 family and its roadmap
Lin also outlined the roadmap for Microchip's PIC32 MCU family, in which "DMIPS performance" and "specification/function" form the horizontal axis and the vertical axis, respectively. PIC32MX1/2 MCU series (66/83DMIPS; far left), which are MCUs with 28-44 pins, provide diversified memory capacities: 16-32KB flash/4-8KB SRAM, or 64-128KB flash/16-32KB SRAM. And they also support peripherals such as USB, I2S, CTMU (charge time measurement unit) and PPS (peripheral pin select).
PIC32MX3/4/5/6/7 MCU series (105/131DMIPS) come with 64-100 pins. The entry-level PIC32MX3/4 MCUs provide memory capacities from 32-512KB flash/4-32KB SRAM, as well as built-in USB controllers. The midrange PIC32MX3/4 models provide memory capacities from 64-512KB flash/16-128KB SRAM, and they support peripherals such as USB, I2S, CTMU and PPS. The high-end PIC32MX5/6/7 models provide memory capacities from 64-512KB flash/16-128KB SRAM, and they support USB, Ethernet and two CAN controllers.
The newly introduced PIC32MZ EC family (330DMIPS) offers memory capacities, from 1-2MB flash/512KB SRAM, and other functions such as HS USB, Ethernet, two CAN controllers, hardware crypto engine and PPS for various application segments, such as consumer electronics, acoustics, factory/building, household automation, environmental monitoring, electric meter, renewable energy control modules, automobile electronics, household appliances and dashboards.
PIC32MZ EC's core architecture, function blocks and developer kits
PICMZ EC is based on Imagination's MIPS32 microAptiv core (codename: M4K) with a 5-stage pipeline design and a clock rate of 200MHz. The microAptiv core which renders computing performance of 1.65DMIPS/MHz incorporates a built-in DSP (digital signal processor) and 159 DSP accelerating instructions for switching between 16bit MIPS16 and 32bit MIPS32 instruction sets, demanding less storage space for program codes. Moreover, the interrupt controller substantially reduces latency of an interrupt operation, enabling better power performance.
Microchip offers entry-level Starter Kits and PIMs for embedded PIC32MZ EC MCUs. The entry-level Starter Kit with integrated debugging and program development functions features scalable designs such as PIC32 expansion board and specific daughter card, USB power supply, 10/100Mbps Ethernet, bi-directional USB 2.0 OTG controller, 4MB SQI Flash and PIC32MZ EC MCU chip for on-line developer and software download.
As a good option for users who are proficient in the Explorer 16 developer boards based on Microchip's 16bit PIC24 and dsPIC or 32bit PIC32 MCU, PIC32MZ PIM can be directly plugged into the Explorer 16 developer board for upgrade of embedded application development by means of PIC32MZ EC MCUs. Multimedia Expansion Board II contains an LCD panel providing versatile features such as high WVGA (800x480), capacitive multi-touch function, VGA (640x480) front-facing lens (300K pixels), Wi-Fi and Bluetooth radio frequency component, 24bit stereo, 3-axis accelerometer and temperature sensor, all of which can be installed on Starter Kit for embedded multimedia applications. Microchip also presents software for decompression of MP3 or AAC, graphical HMI and Internet connectivity.
As summarized by Lin, the brand new PIC32MZ EC is a competitive product family characterized by high performance at 200MHz, 330DMIPS and 3.28CoreMarks/MHz, maximum memory capacities including 2MB flash and 512KB SRAM, maximum 48 channels, 12bit ADC with the sampling rate of 28Msps, hardware crypto engine, and chip encapsulation rivaling 64pin QFN/124 VTLA (9x9mm) and cost the buyer just US$6.68 (unit price based on 10K pieces).
MPLAB Harmony integrates embedded software and hardware
Based on the integrated development environment of MPLAB X IDE, MPLAB Harmony is an integrated interoperable component development framework for Microchip's PIC32 MCUs. MPLAB Harmony coordinates all software solutions including in-house or third-party middleware, drivers, peripheral libraries and RTOS (real time operating system) for interactions. All related third-party software solutions are directly sold by Microchip and they are available at microchipDIRECT, the portal site of Microchip for instant technical support, through which a buyer can be authorized for resale, assistance and warranty.
The embedded system developers are meeting the challenges as follows:
(1) Complexity: Terminal devices are getting more complicated, which requires large numbers of support items and longer development time. Software accounts for 60% of the entire development time.
(2) Rework: When different RTOSs are adopted, new errors may arise in terms of incompatibility between software, and this increases the risk of having to rework program codes.
(3) Inconsistency: When the RTOS, middleware and drivers have to be incorporated onto the same platform, conflicts may arise.
(4) Test drag: 60% of resources in software development are spent on testing and verifying the compatibility of components. If errors are detected when it has already entered the verification process, the time needed to fix them will be 10 times as much as that needed to fix them at the initial design stage.
(5) Fragmented support: it is difficult to obtain all software components from a single supplier's website.
(6) Obsolescence: The future is unpredictable, and when considering a software component, the developer must evaluate future economic risks.
MPLAB Harmony, Microchip's fully integrated development framework, has the following advantages: (1) reduced R&D schedule and expenditure; (2) all in-house and third-party source codes tested, debugged and verified by Microchip without re-work and a user's program codes highly reusable in the Harmony framework; (3) modularized framework effectively enabling stack and integration of software components; (4) pre-tested software components with possible mistakes excluded before verification; (5) Microchip's single-source MPLAB Harmony program codes covering third-party software components; (6) faster time to market because of reduced lead-time.
Steven Lin presented the architecture of MPLAB Harmony as follows: the lowest layer of peripheral libraries (PLIB) consists of PIC32MX and PIC32MZ; the second layer of device drivers consists of Interniche's TCP/IP and freeRTOS or Wittenstein's OpenRTOS; the third layer of Middleware consists of Interniche's TCP/IP and freeRTOS, Wittenstein's OpenRTOS and Micrium μC-OS/III, and wolfSSL's CyaSSL Embedded SSL.
The fourth layer of common system services consists of USB device, USB host, TCP/IP, file system, Wi-Fi 802.11g, cryptography libraries, GDDX/GRC graphics, MP3/AAC decoder, peripheral libraries and math/DSP libraries built in MPLAB Harmony. Furthermore, other components such as Bluetooth audio stack, smartphone accessories, Class B safety and mTouch sensing will be incorporated in the future.
At present, the users can freely access the fundamental framework and most libraries of MPLAB Harmony, which has been available for download from Microchip's website since November 18, 2013.The users have options to purchase third-party developer tools and drivers/libraries (the premium edition). Lin concluded that MPLAB Harmony as a development framework integrating most cross-industry software components provides one-stop shopping services that facilitate porting and reduce lead-time.
Steven Lin, Technical Manager, Microchip