note.txt

// Block info
// Nonce - a hash that when combined with the minHash proofs that
// the block has gone through proof of work(POW)
// 8 bytes => 64 bits

blockchain link
https://andersbrownworth.com/blockchain/blockchain

0x60806040526103e86000557ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff660015534801561003a57600080fd5b506104b88061004a6000396000f3fe


60 80 60 40 52 61 03 e8 60 00 55 7f ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff f6 60 01 55 34 80 15 61 00 3a 57 60 00 80 fd 5b 50 61 04 b8 80 61 00 4a 60 00 39 60 00 f3 fe
 

// STACK
0x60 == PUSH instruction => chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://ethereum.github.io/yellowpaper/paper.pdf
0x52 == MSTORE instruction
0xfd = REVERT
...


// MEMORY

Memory[0x40] = 0x80 // Free memory pointer
Memory[0x00] = code to copy


// how is Block Header Calculated
RLP (“recursive length prefix”) encoding is the main serialization format used in Ethereum,
and is used everywhere - for blocks, transactions, account state data and
wire protocol messages.

How header is encoded
https://ethereum.stackexchange.com/questions/67280/block-header-hash-calculation

Encoder
https://toolkit.abdk.consulting/ethereum#rlp

About RLP encoding
https://medium.com/coinmonks/data-structure-in-ethereum-episode-1-recursive-length-prefix-rlp-encoding-decoding-d1016832f919

Etherem Live view
http://ethviewer.live/


bits, bytes, words
https://www.youtube.com/watch?v=Weyv-V8xz0c

EVMs, and Bytecode
https://www.youtube.com/watch?v=RxL_1AfV7N4

Memory in computer:
https://www.youtube.com/watch?v=F0Ri2TpRBBg


// Truffle :

truffle migrate : build + deploy contract
truffle compile : just compile
truffle console : open console (like browser console) 

// Truffle console :
const instance = await Faucet.deployed() : get instance of Faucet contract
const funds = await instance.funds() : access to field funds
const result = await instance.justTesting()

// add funds
instance.addFunds({value: "2000000000000000000"})
instance.addFunds({from: accounts[0] , value: "20000000000000000"})
instance.addFunds({from: accounts[0] , value: "2000000000000000000"})
instance.addFunds({from: accounts[1] , value: "40000000000000000"})
instance.getAllFunders()
instance.getFunderAtIndex(0)

// withdraw
instance.withdraw("500000000000000000", {from: accounts[1]})

// Web3 API instance :
const instance = new web3.eth.Contract(Faucet.abi, "0xCbf230BfCb4BC68b26baC7F2720570c5A3c9Eb18") : get contract instance with web3 api
const funds = await instance.methods.funds().call() : get field funds.
web3.eth.sendTransaction({to:accounts[1], from:accounts[0], value: web3.utils.toWei('1')})

// Storage
web3.eth.getStorageAt("0x1E9Bfed44D7e2f8bAF438F515C6FB21d5194c3Fe", 0)