Standardisation and integration. Another advantage of x86 architecture is that the standard commercial software is often designed to run on x86-based CPUs. This is also true for many plug-and-play gadgets like printers, keyboards and monitors.
Trivedi shares, “x86 scores over other platforms when the application is very specific and tightly integrated wit legacy counterpart.” If you are looking for easy integration and a wide range of peripherals like lots of GPIO, PCI, UART, analogue-to-digital and digital-to-analogue converters, and storage, the x86 solution is a good choice.
Also, x86 architecture is highly scalable. That means if you have designed an embedded system based on a small x86 processor like an Atom, you can easily replace it with a more powerful processor like Core Duo without much of redevelopment.
Since every processor in the ARM family is individually developed with specific features, it cannot be scaled down or up. For an ARM-based solution, you need to know the exact need of the embedded solution.
Coming to a real-time embedded application, there is hardly any instance when you have to upgrade just the processor of the application. By its very definiion, embedded applications are developed to perform dedicated tasks.
Booting x86-based system. x86 usually comes with basic input/output system (BIOS). Leonid Rosenboim, an embedded systems entrepreneur, says, “BIOS is very useful for booting, but it is the software that you do not control, and may need to change when it is undesirable. This could prevent you from having full control over some resources. Some types of BIOS could actually continue to run in the background along with your RTOS and application, causing occasional mysterious deadline slips. “
In x86, the BIOS can be replaced with a less expensive, lighter-weight and much faster set of boot code like coreboot.
Steve Goodrich, principal, Sage Electronic Engineering, explains, “You wouldn’t use coreboot in every case where you need a BIOS. A BIOS is typically more flexible and intended to work with systems on which the hardware can vary from one boot to another, while coreboot is targeted at systems on which the hardware does not vary, such as an embedded device.”
Commercial-off-the-shelf (COTS) board. Software development on x86 platforms has been quite convenient. However, “The complexity of hardware design and competition from Taiwan prohibits designing of the hardware locally,” shares Sinha. He explains that since x86 platforms have been very popular in digital signage, industrial and other such applications, Taiwanese are offering these products at a very low cost. For example, you can buy a complete motherboard for less than Rs 4000. However, if you have to build it locally, you won’t be able to match the price-point. They have a very good infrastructure to lower the costs.
Adding to the advantages of COTS x86-boards, Sharma shares, “These are extremely useful when you have to deliver a system in a short period and the hardware cycles are unacceptable, volumes are low and the non-recurring cost of development cannot be offset.” He also feels that time-to-market pressures obviate the need for x86 in such a situation.
The disadvantage of COTS boards is their short life of 3-6 months causing you to retest your solutions every time you try a new board. Rosenboimshares, “Most often, an x86 board is chosen for its low cost and low volume, but it also has a short product life, forcing you to replace discontinued boards with new ones that cause unplanned and non-budgeted re-engineering costs and associated risks.”
