Hi Eng.suhail,
You have several options.
MDK-ARM includes RTX RTOS example projects for a LPC2130 board (the MCB2130).
I also got a few hits when searching for FreeRTOS and LPC2138.
Hope this helps,Johannes
You can try ucos. It's fully documented and free to get souce code that it has been transplant on nxp's soc.
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