AllGo Embedded Systems was founded by professionals with a total of 70+ years of experience in DSP and embedded system development. Their solution development experience spans automotive infotainment systems, high-definition video, short-range wireless, consumer audio systems and CD players. Darshak Vasavada, co-founder of AllGo Embedded Systems, speaks to Dilin Anand of EFY about the company.
Q. What is your USP?
A. AllGo Embedded Systems is a 7-year old company in embedded market media space. Today we do complete product designing including the hardware and software, and outsource manufacturing in embedded market media and DSP space. Our main expertise is in Hardware and Software co-design.
Q. What was your first product?
A. Our first product was a portable media server. Subsequently we did digital Photo frames and media players. Currently we are working on a tablet. We converted one of our platforms into a low cost tablet designed for the Indian market. The Stamp is our first product that was fully developed from scratch including the hardware, circuits, and mechanical design. Everything except manufacturing is done in-house by us.
Even though manufacturing was outsourced, we did not want to compromise on quality, so all the key components like the processor, LCD, battery, memory and the power management circuits had been identified by us. Other components like passives, discretes, connectors were left to the factory to get the best prices.
Q. What strategies did you use to keep the price down on your tablet?
A. We used a highly-integrated processor based on the ARM9 core. This processor, the Freescale MX233 was originally intended to be used for Digital Photo frames and Internet radios. So we used this particular inexpensive processor and then proceeded to port Android on top of that.
We used our expertise in DSP and Firmware to squeeze performance out of the MX233. So we did some optimisation in the software. For example, Android 2.2 requires a GPU, but our SoC does not have a GPU. So we optimised those parts of code, which use software libraries for graphics.
Likewise we used a pixel pipeline on the processor, used some optimised video codecs to improve the performance. This processor itself was not designed to support VGA – the data sheet states that it can go up to VGA. But we changed it so that it can support WVGA.
Largely, we picked up an integrated device and got better performance out of it through software optimisation, which allowed us to greatly reduce the chipset costs. So rather than buying an expensive high-end processor, we were able to achieve the required performance from an in-expensive processor.
Q. Are there any other advantages that the device gained from this strategy?
A. The other advantages that we enjoy due to using this strategy are that we could use lower clocked processors to achieve the same performance as higher clocked ones. Then there is the reduced power consumption which elongates battery life. Moreover, it also improves the charging circuit performance. For example, if you use the device for reading at night you could get 7-8 hours of up-time.
Q. Were there any difficulties when you ported Android 2.2 onto an ARM9 processor without a GPU?
A. Yes, there were. Getting an acceptable performance was a challenge. Initially, the touch response was not good enough. Then the application took a long time to load, the graphic would be slow and the video would be jerky. All of these problems had to be solved.
Q. Why did you go for a resistive touch screen over a capacitive one?
A. We designed this product to perform optimally for the use-case for which it was designed. This device was not intended to compete with higher end tablets but for use in enterprise environments where cost is important. What we looked at doing was that where all this tablet could go, and in which all solutions this tablet could be deployed meaningfully. As long as the use-cases are properly taken care, this device achieves its target.
One of the use-cases was to conduct a survey. So, the device gives a good battery life since in a survey you would want to take it around. Also, in a survey you have a questionnaire in front of you and the answers are shown as options in front of you. Psychologically you are pressing and therefore you apply the pressure to activate the resistive screen. In this case using a capacitive screen would be unnecessary as you don’t really need multi-touch gestures or high-end screens.
Q. Is there any particular vector which recently provided a technical challenge for you?
A. We did face one particularly challenging problem at our automotive side when we ported Android for an automotive system. The challenge was to boot-up Android very fast as the device has to be available as soon as the ignition occurs and the car turns on. Those devices do not have the option to go on stand-by as when you switch of the car, they turn off completely. The requirement is that the device should be booted up within 7-8 seconds.
So we set-up a working version of Android, took a snapshot, and booted up from that snapshot. That method did work and Android did come up, but all the other devices had to be switched off at that point. Ideally, all the other devices have to independently come up and then the devices have to synchronise so that they (file system, GPU, etc) are in the same state.
Q. Could you give us an instance when you faced a challenging bug as you ported Android?
A. One of the trickiest bug appeared when we unmounted the filesystem as it shutdown; one particular filesystem was not unmounting because one application somewhere was using it. The problem was that it was not using the filesystem directly. Instead, it was using it through memory map. So if you look at the list of open file-systems and tables it would show all of them to be closed. But one particular application which was part of the DVM, had mapped the filesystem onto the memory. Figuring that out and working around it was very interesting.
Q. How many design engineers do you have working here?
A. We are entirely an engineering house so around 90 per cent of us can code. That would make up around 70 design engineers.
Q. What is the average experience of these engineers?
A. Around 3-6 years.
Q. Do you hire freshers?
A. We absolutely take in freshers. Freshers come in with a lot of energy, and a lot of willingness to learn. And we have a culture that we feel proud of and it is much easier to get freshers into that working culture. Essentially the work involves learning all the time.
Q. Do you have any product in your pipeline right now?
A. Stamp 2 is definitely there. The next requirement would be a larger and faster device capable of handling better graphics and animation. We have 2 models of Stamp 2, a 7-inch version and a 10-inch version with capacitive touch screen.