Litecoin proof of work

[pieppiep]

I'm interested in the proof of work concept used in the cryptocurrencies.
The one used for bitcoin I understand and implement if I want.
The one used for litecoin is a bit harder to find.
Until now I just find I should replace the sha256(sha256(block of 80 bytes)) with scrypt(block of 80 bytes).
The problem is the scrypt hash, I can't find a clear description.
I know it somehow generates a pseudo random block of data with a length of 128kB and does some pseudo random mixing of that block.
The sourcecode of the cpuminer I found is to optimized for me to read.
Does anyone have a link to some pseudo code like the one on http://en.wikipedia.org/wiki/Sha256 but for scrypt?

[pooler]

A thorough description of scrypt is available at the following address, along with a reference C implementation:
http://www.tarsnap.com/scrypt.html

The scrypt-based proof of work is described in the Litecoin Wiki:
https://github.com/coblee/litecoin/wiki/Scrypt-proof-of-work