How multi coin ICO are organized?

[wimpythunder]

There are some ICOS who are accepting ETH as well as BTC and they are issuing ERC20 tokens on Ethereum.

It is clear how it works with Ethereum (eth in -> smart contract -> token out)

How tokens issuing process is handled for bitcoins? Is it manual process or is it automated via some kind of code? How does it actually works?

[PaulDroid]

This is explained here: https://ethereum.stackexchange.com/questions/26308/ico-crypto-currencies-accepted-during-the-sale-eth-btc-or-even-fiat/26610#26610 probably you should use Google before asking such question 

[Jdope]

I think its mostly manual, they calculate a dollar rate and do the conversion with the rate at the time of sending. One of the icos i watched was sending you something like a code in which you use in sending to verify it was from you. neat stuff but still manual and more prone to errors