ARM Cortex memory requirements for Embedded Linux

Hi,

I want to have embedded linux with C++ application on 32 bit ARM cortex based microcontroller.(price < $20)

I got to know through google search that I need to use the external RAM and FLASH.

I would like to know what would be the memory requirements (On board RAM, ROM and external RAM and Flash) of such application?

Suggest any links to for me to study.

This is the smallest Linux I know: **broken link removed**

EDIT: Sorry, that linux is not particularly small, but it runs on minimum resources. The smalles Linux I've seen fits on 16 megabytes of flash and that system has 32 megabytes of SDRAM. **broken link removed**

an LPC1788 is $14 and has CAN, EBI/EMI, Ethernet, I²C, Microwire, MMC, SPI, SSI, SSP, UART/USART, USB OTG, Brown-out Detect/Reset, DMA, I²S, LCD, Motor Control PWM, POR, PWM, WDT.

So you have your choice of USB or SD for mass storage, ethernet on chip, kernel on chip (512K FLASH, 96K RAM on chip), up to 1G of SDRAM (32bit data, 80MHz), and an LCD controller all on chip