Yes, it is implementable, but how?

Reading the third chapter of this book, I’m astonished that ECC (ECDH) is implementable on Chipcon CC1010 chip which consists of an 8-bit 8051 processor core with a built-in radio transceiver and a hardware DES engine. It containts 32 kb of flash memory for storing programs, 2048 bytes of SRAM external to the 8051 core (XRAM), and 128 bytes of internal SRAM (IRAM).

Now the question is, without using any additional extra hardware, how to build codes calculating those complex operation of ECC that fits those small memories???

[screaming in horror…]