标签: Microchip

My firiend Mike Hibbett is a senior software engineer and a columnist for the electronics and computing hobbyist magazine Everyday Practical Electronics in the UK.   Mike has a passion for developing highly reliable products, so I was very interested to hear about his Kickstarter campaign for a low-power, low-cost (LPLC) PIC18 development board .     As you are certainly aware, there are a plethora of microcontroller development boards available on the market, so why did Mike feel moved to create yet one more? "None of them quite hit the spot for me," he says on his Kickstarter page. "They were either too small, too power hungry, too expensive, or just too limiting." None had the "Goldilocks" combination of features and capabilities.   Mike wants to build circuits that run off a couple of coin cells for months or AA batteries for years. In the case of cost, he wants something affordable enough that he can deploy a new board in each project and not have to reuse a board from another project just because he can't afford an additional unit.   He also wants "lots of code space" and the ability to use "a proper, professional development environment. I write complex code, so I expect a decent debugger" Last, but certainly not least, he likes to make tiny projects. "Some of my stuff ends up in portable applications and even magic tricks."   The end result is the board shown above. This little beauty is based on a Microchip PIC18F27J13 processor, which is small yet powerful. The PIC18F is quite a powerful processor for its size and cost; it runs at 48 MHz, can process 12 million instructions per second, and provides 128KB of Flash program storage. Its architecture is designed to facilitate being programmed in C.   Though the LPLC board itself is tiny, it still offers access to more than 20 I/O pins that can be used to implement myriad cool projects. Consider the following example.     The above image shows an LPLC prototype board implementing a simple, battery-powered, single-channel oscilloscope driving an equally low-cost color LCD display -- all implemented on a standard breadboard. From Mike's Kickstarter project page, I see that there are only six days to go. If you are interested in laying your hands on one of these little LPLC beauties, now is the time to do so.

In my recent column , I related my plan to load the robot I'm building with a cornucopia of sensors. The problem with having a lot of sensors is that we have to process the raw data they are receiving and turn it into useful information. If we're not careful, the robot's main processor will be spending all of its time wading through data from the sensors without having any computational resources free to do anything useful. One solution, as we discussed, is to have a small processor associated with each sensor, and to pre-process all of the raw sensor data into useful information like "Eeek! There's a big hairy object approaching at speed from a northwest direction," thereby leaving the main processor free to make executive-level decisions like "Run away!" But even if we do offload the low-level processing tasks, we could still overwhelm the main processor if we deploy a sufficient number of sensors. The solution is to use a faster, more powerful processor for your main controller, but what are the alternatives that are open to us? Mainstream Arduinos I am currently the proud owner of an Arduino Uno , which is based on an 8bit ATmega328 processor. This little scamp offers 14 digital input/output pins (of which six can be used as PWM outputs) and 6six analogue inputs. It uses a 16MHz clock and boasts 32 KB of flash memory and 2 KB of SRAM.   The Arduino Uno. Although the Arduino Uno is almost inconceivably more powerful than the processors of my youth, and it's more than powerful enough to satisfy the requirements of a wide swathe of users, it's a tad lightweight with regard to the number of sensors I intend to deploy on my robot. One option would be to move up to the Arduino Mega , which offers 54 digital input/output pins (of which 14 can be used as PWM outputs), 16 analogue inputs, and four UARTs:     The Arduino Mega. Once again, however, the official Arduino Mega is based on an 8bit ATmega1280 processor running at 16MHz. Another alternative is to use an Arduino Due , which is based on an Atmel SAM3X8E ARM Cortex-M3 microcontroller:   The Arduino Due. This little beauty offers 54 digital input/output pins (of which 12 can be used as PWM outputs), 12 analogue inputs, and 4 UARTs. In addition to the fact that it's got a 32bit data path, the Arduino Due employs an 84MHz clock and boasts 512 KB of flash memory and 96 KB of SRAM. Arduinos on steroids One of the great things about the Arduino is that everything is open-source. Due to this, a wide variety of Arduino-compatible development boards have appeared on the market. One set of boards that really makes my mouth water is the chipKIT family . The original members of the chipKIT organisation were Microchip Technology, Digilent, and Fubar Labs. These companies have since been joined by other members, such as the folks from element14. In fact, the most recent Arduino-compatible chipKIT platform—the chipKIT Pi—comes from Microchip and element14. The chipKIT Pi can interface directly to the Raspberry Pi's I/O expansion header, but that's a story for another day. In addition to the raw processing power of the chipKIT platforms (as discussed below), the thing that really differentiates these little beauties from the herd is the amount of effort the chipKIT folks put in to making the transition from Arduino to chipKIT as seamless as possible. You do need to download a new development environment called MPIDE (multiplatform integrated development environment), but once you've done so you'll find it looks almost identical to the standard Arduino software. But it's the boards that make you drool with desire. Let's start with the chipKIT Uno32 , which is the same form factor as the Arduino Uno and is compatible with many of the standard Arduino shields. (The reason for this "many" qualifier is that some shield creators write libraries that talk directly to the AVR hardware, which sort of goes against the Arduino philosophy of keeping things portable by writing to the abstraction level.)   The chipKIT Uno32. The Uno32 board is based on the powerful PIC32MX320F128 microcontroller, which features a 32bit MIPS processor core running at 80MHz along with 128 KB of flash program memory and 16 KB of SRAM data memory. One thing that immediately caught my eye was the chipKIT Pmod Shield-Uno . This is an input/output expansion board for use with the chipKIT Uno32 that provides five 2x6 Digilent Pmod connectors (it also provides access to the I/O connectors available on the Uno32 as well as connecting to the I2C bus supported by the Uno32).     The chipKIT Pmod Shield-Uno. Have you seen all of the Pmod modules offered by Digilent? (You can also get modules from other companies like Analog Devices, Maxim, and Texas Instruments.) These include GPS receivers, 3-axis digital accelerometers, 3-axis digital gyroscopes, 3-axis digital compasses, microphones with amplifiers... basically a bunch of things I intend to add to my robot. At the other end of the spectrum we find the chipKIT Max32 prototyping platform . This little rascal has the same form factor as the Arduino Mega board and is compatible with many Arduino shields as well as larger shields for use with the Mega boards.     The chipKIT Max32. The Max32 board is based on the powerful PIC32MX795F512 microcontroller, which features a 32bit MIPS processor core running at 80MHz along with 512 K of flash program memory and 128 K of SRAM data memory. In addition to supporting 83 inputs and outputs, the processor provides a USB 2 OTG controller, 10/100 Ethernet MAC, and dual CAN controllers that can be accessed via add-on I/O shields. Wow! My head is spinning. I feel like I'm spoilt for choice. To be honest, I actually think I might end up using a hierarchy of controller boards (in addition to the microcontrollers on the sensor boards) with one in overall charge and the others each delegated to focusing on a certain task. This is all going to take some thinking about—watch this space for ongoing developments.

  去年参加的Designspark的比赛，获得的奖品！  

        由于需要用到USB3.0接口进行开发，所以换过一台主机。对于任何一个开发人员来说，这都是一件非常不情愿的事情，毕竟熟悉了原来主机的系统以及软件操作形成习惯后，要换到另一台主机上必然会遇到很多问题。         现在问题就来了，在新的PC主机上安装好MPLAB IDE后，然后再安装了mplabc18-v3.40，直接打开原来的工程文件，选择好编译工具后，马上进行了编译不能通过。问题如下  使用的芯片是PIC18F14K50带USB接口的。问题可能在于链接文件不对，所以需要安装microchip-application-libraries，是pic的库文件和一些例程。里面有包rm18f14k50.lkr这个文件需要放在C:/mcc18/lkr/路径下面。这样再次编译一下就OK了。

Just to make sure that we're all tap-dancing to the same drum beat, let's recall that Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments. Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The boards can be built by hand or purchased preassembled; the software can be downloaded for free. The hardware reference designs (CAD files) are available under an open-source license and users are free to adapt them to their needs. There are a variety of different Arduino boards. Two of the most popular are the Arduino Uno and the Arduino Mega. Different implementations are available from a number of suppliers. There are also a bunch of plug-in daughter cards called "Shields" – again, these are available from a number of suppliers. The whole Arduino concept has attracted a large following. One problem, however, is that just about all of the existing Arduino boards are based on relatively low performance 8bit microprocessors, until now... The thing is that users have been begging for more power and performance, and the folks at Microchip and Digilent have risen to the challenge magnificently by launching the first 32bit-microcontroller-based, open-source development platform that is compatible with Arduino hardware and software. The first board is the chipKIT Uno32 , which is a clone of the Arduino Uno board, but with much higher features and performance (32bit processor, 80MHz, 128 KB Flash program memory and 16 KB RAM, with two each of the I2C, SPI and UART peripherals). Amazingly this board is priced at $26.95 each (the average price for an Arduino Uno is around $29.95).   The second board is the chipKIT Max32 , which is a clone of the Arduino Mega board, but – again – with much higher features and performance (32bit processor, 80MHz, 512 KB Flash program memory and 128 KB RAM, with USB, CAN and Ethernet communication, as well as 5 each I2C, 4 each SPI, and 6 each UART peripherals). The chipKIT Max32 board is priced at $49.50 each (the average price for an Arduino Mega is around $69.95).   Both chipKIT boards can be ordered today ( Click Here ). Additionally, the open-source software for both boards is available today ( Click Here ). chipKIT Network and I/O Shields are expected to be available this month.