electrodesigns.net

I just started to use Cadsoft Eagle for PCB design some weeks ago. I tried many times in past but somehow left in between due to lack of interest. This time, however, I had a project in hand and the client requirement was to do it in Eagle. I am more used to the Diptrace software and I have reasons to like it. But Eagle is also a very popular PCB design software so I desire of using it.

In Eagle, I specially liked the schematic section as it looks very pretty at the end. It looks surely much more professional than drawn in Diptrace. Most of the hobby projects on Internet with pretty looking schematics you will see are designed in Eagle. Eagle saves its library files in XML format. So one can copy/paste a chuck of XML in the file to create a new footprint. Then can edit the part in the library editor of Eagle. (continue reading…)

Often I have thoughts where to invest my “pocket money” and more importantly time and effort. The ARM architecture, I think, is the answer. Currently a kit of TI’s LM3S8962 Stellaris series (which was LuminaryMicro when I had bought this demo kit, ahh I can’t forget LuminaryMicro, recession has some unforgettable memories in my mind) rests in front of me and, as always, am “admiring its beauty”. So “why” is the question:

• ARM is well penetrated and it will stay in market for a long time (at least a decade, I think).
• The development tools are everywhere easily available and those are cheap. So you can get started easily.
• Well supported architecture among IC vendors, in-fact, it has become a “fashion” to launch MCU based on Cortex-M3. Look at TI, NXP, ST, EnergyMicro etc. etc… They are “running” hard to catch it.
• ARM is well heard among tech managers so it will increase an engineer’s market value. Somehow I realized that if I want to stay in this field (embedded systems), then I will need to maintain my market value. Otherwise somebody else is always there ready to replace me with lower pay.
• All other advantage which something “in” may have.

So I have decided to “target” this dimension more intensely in the coming times.

I have been designing PCBs for around 8 years now. My first experience was with OrCAD 9.x. OrCAD is very powerful tool and widely used in electronics industry. However, somehow, I was a little tired of it as it seemed to me based on old technology. Working in the schematic capture section was not very easy and layout was even difficult. Components library creation could easily lead me to head scratching.

It was some 3 years back. I was really looking for a software which is easy and just does the job. One day I found Diptrace. I learned it very quickly as it was very easy. The user interface was very intuitive and seems to be a really modern interface built-in “this era”. The PCB layout was also very easy, nothing less nothing extra, just every necessary tools available there. The component and footprint library creation was also very easy. Most importantly the cost of software was affordable. It increased my efficiency and reduced the headache of PCB design.

Diptrace has very good import/export options. One of the great option is Route-> Electra/Specctra Interface-> Export Autoroute DSN and Import Autoroute SES. I use this option for complex designs to export my unrouted board to Specctra, which is a great autoroute tool, route in it and import back the SES file into Diptrace for fine tuning. This is one of the great features of Diptrace I really missed in Eagle.

There are, however, a few things which I wish could be improved.

• First is to improve the 3D viewer section. The graphics rendering should be improved to make it look more closer to the real PCB.
• Diptrace currently does not support built-in 3D object creation, which I think, can be a big bonus.
• The third and last is the back annotation. There come times when we need to design the layout first and schematic later. In this case Diptrace is not going to help you much.

All in all, Diptrace is a very good tool for beginners as well as experienced engineers. It saves times, makes PCB design an enjoyable experience and does the job which you expect from a professional designer.

The 32 bit hobbyists? What does it mean. I mean to say the near future generation of hobbyists which will do minor tasks like blinking an LED or displaying some text on LCD on 32 bit microcontrollers. But why 32 bit when there are hell lot of 8 bit and 16 bit MCUs out there? Because 32 bitters will be so common and cheap that every “”micro-aware” guy will choose only these buddies. They are now very power efficient, come with many peripherals and easy to solder “hobbyist friendly” pin packages.

So what are the options?

Many vendors have “jumped into” the band wagon of 32. Everybody is there with there own “unique” offering. However, by features and capabilities they are almost the same.

Vendors like TI, NXP, ST, Atmel are providing solutions with ARM Cortex-M3 based MCUs with Atmel has another option of it AVR32 offering. AVR32 business has not been very successful till date. However the Cortex-M3/4 has just shaken up the MCU industry and it is seen everywhere. Especially, TI’s Stellaris (formly LuminaryMicro) is very impressive.

Microchip came up with a unique solution called PIC32 based on MIPS M4k. Well, MIPS is an old guy but completely unheard in MCU market. It’s great architecture, well penetrated in deep embedded and high end markets like data server, networking devices with established 32 bit AND 64 base. However, Microchip did several smart moves to “encash” its 8 an d16 bit “base” into 32 bit. They kept the same style of coding, same IDE, and same concept of hobbyist friendly MCU with packages down to DIP-28. 32 bitter in DIP-28, amazing! Here is a small comparison of PIC32 and Stellaris series.

However, there are some other vendors with a some difference. Yes, I am talking about Freescale’s ColdFire.

To summarize, there are many other vendors with great 32 bit offerings. Why buy an 8-bitter when almost in the same price, more powerful, easy to solder (as well) and well supported option is there.

So, welcome 32-bitters!

The largest part of my career was to design network connected devices also called “internet of things”. Ethernet has a very effective way to collect alarms and pass to a remote server, translate other protocols like RS232/485 to TCP, alarm systems, home automation and other applications. I had the chance to “taste” different embedded microcontrollers and TCP/IP stack to encounter. Device in the list include PIC18, PIC32, Stellaris controllers while the stacks include Microchip’s propriety TCP/IP stack, lwIP, uIP.

uIP is the simplest and smallest stack with minimal footprint, however, the available stack APIs are limited.

lwIP is probably the most used embedded TCP/IP stack used by dozens of vendors. Because of open source nature and the “operating system emulation layer”, it is adopted by many MCU vendors including some 8051 variants and ARM “cousins” use the same stack with necessary relative adoption.

Microchip TCP/IP has the limitation that it can be used only on Microchip product. However, it is the most complete and greatly organized TCP/IP stack I have seen. It has every thing, every set of protocols a developer may need with the great thing inherited by Microchip is the great documentation; everything very well explained with examples. The stack has built-in support for Ethernet as well as WiFi. Microchip has its own WiFi modules available which can be integrated with PIC MCUs via SPI bus. The stack fully supports TCP, UDP, HTTP, SNMP, SNTP, and virtually every protocol which an average Embedded Systems Engineer needs.

In a practical implementation of Ethernet connected devices, I came across on implementation of lwIP over Stellaris. One thing which stung me was that you need to build the file system (fs) using “makefsfile” utility just like “MPFS2″ utility. But it will give you plan C files to be compiled with source to burn into the device. Unlike this MPFS2 give a separate .bin file which you can upload onto the device “on-the-go”. This seems to me a big advantage of Microchip tools over lwIP implementation for Stellaris.

Welcome to the internet of things!

MIPS architecture has been in shadow for quite some time. But this was not to remain for long. With the advent of 3G and 4G telecom industry and the new small internet connected devices called tablets, smart phones etc, MIPS has reemerge as leader in embedded market. Ingenic is one of those players. From JZ4750 to JZ4770, they have launched very efficient and extremely power efficient multimedia SoCs which took market as storm. The application products of Ingenic SoCs are Cruz Table and new Novo7 Tablets with Android 4.0. Andoid is well followed by MIPS team and they are providing the latest update (currently 4.0.3). This can be a great success for MIPS and revival of its golden era.

PIC32 and Stellaris series both lie between the high-end microprocessors and low-end 8/16 bit microcontrollers. Both architectures are designed to be best fitted into microcontroller and deep embedded applications. However, they are powered by the cores of very different vendors competing in architecture market.

PIC32 is the flagship product of Microchip Technology Inc. while Stellaris is now owned by industry leading Texas Instruments (TI). PIC32 is powered by very efficient M4K core from MIPS while Stellaris is powered Cortex-M3 from industry standard ARM architecture. Both the series have their advantages and disadvantages.

Architecture wise both the controllers are very similar with M4K a little more efficient with 1.5+ DMIPS while Cortex-M3 with 1.25 DMIPS performance. PIC32 can pull with ful 1.5 DMIPS performance while Stellaris is a bit lagging.

PIC32 has a great base of 8/16 bit PIC developers. No doubt PIC is the king of 8 bit market. Microchip offers the same MPLAB IDE for all 8, 16 and 32 MCUs. Stellaris, although, does not have such base, but ARM is most widely used 32 MCU. So Stellaris has the advantage of a huge number of “brotherly” MCU vendors like NXP, Atmel and ST etc.

The peripheral sets are also very much the same with emphasis on communication peripherals like CAN, Ethernet, I2C, USART, etc. So one can do pretty much everything he wants to do. Both MCU series have lots of memory around upto 512KB with Stellaris an advantage of using external program memory as well. PIC32 lags in this point that external “program” memory can not be interfaced with it.

Stellaris have a great upward market. With the helm of devices with Cortex-A5/A8/A9 which provide best properties of application processors. This area is somewhat weak for PIC32. With Microchip, you end up with MCUs only and getting upwards means changing vendor, tools and everything. Though working on application processor is really different from that on MCUs, from Microchip one really needs to look around where to go? (Here I tried to answer this question). There are some very popular and successful stories like Ingenic from China or Alchemy series from NetLogic, but they are not great in number. One thing different about MIPS is that they are well penetrated in the market but only in deep embedded applications. It is difficult to find them into general purpose MCU market as one can find ARM. Often MIPS licensees ignore to mention the great power of MIPS behind their products’ “tag” which, I think, is bad marketing effort from MIPS team. But they are there and there is no doubt about that. So the best available option is to move to extremely power efficient and feature enriched media processors from Ingenic.

Anyways for an MCU user PIC32 and Stellaris offer almost the same. Both are solder friendly and hence hobbyist friendly. But they deserve a good presence in professional markets as well.

For 8/16 bit PIC users, PIC32 is a great step forward. For 8051/alike lovers, Stellaris is good, though it’s not a bad idea to taste both of them and decide yourself what suits your requirement and which is more in-lined with your previous experience.

I have used Microchip’s PIC microcontrollers for more than six years now and I have found many good things about them which are summarized below:

1. They have free development tool called MPLAB
2. The programmers/debuggers are cheap, currently you can buy PICKit3 programmer/debugger prob for less than USD50.
3. They are some wonderful and free stack libraries like those of Ethernet, Wifi, USB, serial and what not.
4. There is hell lot of free code to get started and finish the job quickly.
5. Can you image a 32 bit microcontroller with 61DMIPs of power and DIP28 package? Yes, microchip has that to offer. PIC is very “hobbyist friendly”.
6. Microchip is a big company and a stable one too. During the last 2009 economic crunch, it remained one of the few tech companies which kept growing. So their products as well as your expertise will remain long lasting.
7. One of the reason of Microchip’s success is their quick support. I can remember the days when they newly launched WiFi modules. Infact the modules were not even officially launched from Microchip’s website rather a third party called ZeroG Wireless had built the modules. Microchip provided me wonderful help. Later ZeroG was acquired by Microchip and products were re-branded.

Electronic and computer engineers often need some tools to debug their hardware and/or firmware. I have used several free tools to this purpose and trying to presented here. These apps are for Windows 32 bit.

TFTP.exe

Often we need to update the firmware of embedded device through TFTP (trivial file transfer protocol). TFTP.exe utility is a stand alone application can do our job quite easily. It also very light weight.

Advanced IP Scanner

IP scanner is good tool to find our devices present on network or to find out the IP of an unknown device.

COM Port Toolkit

Another very useful utility for serial debug and monitoring. It has options to display and send ASCII as well as HEX data. Data can be sent once or continuously on set periods.

Hardware Group Virtual Serial Port

It is a very handy tool when the hardware you are using talks on TCP while the application can only communicate on serial. For example you want your serial data logger to be accessed via TCP network. For that purpose you have connected a UART-to-TCP bridge to it. Now the software provided with the hardware would most probably support serial communication.

This utility will help you to connect to the UART-to-TCP bridge by providing IP address and port number and will give you an available COM port. Now you can use this virtual COM port with you software application already provided with the hardware.

Herculus

Herculus is an all-in-one utility which contains serial data viewer, TCP client/server as well as UDP utilities.