looking for technical info

[CanaryInTheMine]

could someone point me to where I can see code /pseudo/code for the calculation of a hash.  step by step would be awesome, but anything would be helpful too.

[jackjack]

could someone point me to where I can see code /pseudo/code for the calculation of a hash.  step by step would be awesome, but anything would be helpful too.

A hash of what?
Block, transaction, address?

[CanaryInTheMine]

could someone point me to where I can see code /pseudo/code for the calculation of a hash.  step by step would be awesome, but anything would be helpful too.

A hash of what?
Block, transaction?

block

[etotheipi]

Are you talking about SHA256?  The wiki is always a good place to start for that:  http://en.wikipedia.org/wiki/SHA-2

If you're talking about something more specific to BTC, there are three places that hashes are used that I can think of, off the top of my head:

(1) 80-byte block headers  {sha256(sha256((...)}
(2) Full transactions       {sha256(sha256(...))}
(3) Converting public keys to BTC addresses  {ripemd160(sha256(...))}
 

You can see illustrations of a full Transaction (2) and the conversion from ECDSA public key to BTC address (3) in my post: 
https://bitcointalk.org/index.php?topic=29416.0

[WakiMiko]

blockhashing example in C: https://gist.github.com/1173353