As per your questions:
- do all ARM boards support embedded OS like embedded linux & winCE without processing/memory restrictions?
No!
MMU-less ARMs can run variants of µCLinux which require a minimum of 300kB RAM, however it is a bare minimum system just enough to boot the kernel.
A more typical ARM/Linux system requires a minimum of 2MB of RAM , 16MB to 32MB of RAM for an viable development platfrom and an equal or greater amount of FLASH.
Windows CE requires a minimum 32MB of RAM and 32MB of FLASH.
The problem is many ARMs do not have an external memory bus for additional RAM, so you are stuck with what you have.
- i'm a begginer in arm, so does it matter which family to start with? (i.e. starting with ARM 9 better than ARM 7 as it is more advanced, & same for Cortex A8 when compared with cortex M4)
Note: i want to get to advanced level in ARM development.
If you wish to run full blown OSs like Linux or Windows CE, first narrow the field by selecting ARM variants with the appropriate amounts of RAM and FLASH. Or if the particular device has an external memory bus to supplement both its internal RAM and FLASH.
The narrow down the field even more by defining your required peripherals and features
- what is your opinion concerning buying ARM boards from genuine companies only not chinees?could you just give me some trusted companies with good support other than ATMEL & Kiel?
I own several of the Atmel and KEIL boards and they do produce an excellent ARM development boards, the downside is they are quite expensive.
If you like Atmel ARMs, the SAM9 ARM926, checkout Olimex's
SAM9-L9260 DEVELOPMENT BOARD or
SAM9-L9261 DEVELOPMENT BOARD.
Olimex, an EU company, also sells several other boards based on various variants, NXP's LPC series, **broken link removed**.
One of my preferred companys to purchase ARM Linux/Windows CE development boards, which I've used in several commercial projects, is
Technologic Systems.
I've purchased most of their ARM boards, they are of excellent quality and their technical support is top notch. They use both ARM9 and Cortex-A8 variants in their products.
Checkout the following:
TS-TPC-8900
TS-7800
ARM Single Board Computers for Embedded Systems
One other company I've done business with in the past which offers high quality development boards:
Embedded Artist
LPC2478 Developer's Kit
LPC3152 Developer's Kit
LPC3250 Developer's Kit
Another vendor to keep an eye on is TI, who has their
TI Deals, which has offered deep discounts on ARM dev boards.
I've bought quite a few development tools and boards from TI, but have only recently dabbled with their ARM variants, so my advice in this area is limited. I will say everything I have purchased from TI, MSP430 and DSP boards and JTAG equipment has been top notch.
Are you a student? If so I can refer you to an excellent deal for a ARM JTAG programmer/debugger.
BigDog