Ethereum raw transaction structure

Question

I'm trying to learn the raw transaction data structure for Ethereum. Here my transaction (ropsten network) :

0xf8691285012a05f2008307a12094b75fe87f44cb2003f3472424261f021d2100ce5a80843ccfd60b2aa0fce2a70cde55dc86a203d2387469c36da00e9a9f3536b867f6761c314b1f1423a07b85742fd48a687b8daa097d1fb9d4b5135de6deb5b6fd16dd0f28d6c28727b6

0x

f869 ???

12 (nonce)

850 ???

12a05f200 (gasprice)

830 ???

7a120 (gas limit)

94 ???

b75fe87f44cb2003f3472424261f021d2100ce5a (to)

8084 ???

3ccfd60b (data because smart contract interaction)

2a (v + chainId*2)

a0 (160 in hex)

fce2a70cde55dc86a203d2387469c36da00e9a9f3536b867f6761c314b1f1423 (r)

a0 (160 in hex)

7b85742fd48a687b8daa097d1fb9d4b5135de6deb5b6fd16dd0f28d6c28727b6 (s)

What are other line ? Like "f869" , "850" after nonce, "830" after gasPrice, "94" before TO ans "8084" after to?

Answer 1

0x
//  https://eth.wiki/fundamentals/rlp for more on f8
// 0xf8-0xf7=1byte=2 chars which tells you next 2 chars is the length of the paylaod
f8
// length of payload. 0x69=105bytes=210 chars. 
69
// Nonce. 1byte
12 
//0x85-0x80=133-128= 5bytes=10chars= GAS PRICE
85 012a05f200
// 0x83-0x80=131-128=3bytes=6chars= GAS LIMIT
83 07a120
// 0x94 - 0x80=148-128=20bytes=40chars= TO
94 b75fe87f44cb2003f3472424261f021d2100ce5a
// this should be value. empty valu, string is represended as 80
80 
// 0x84-0x80=132-128=4bytes=8 chars= DATA
84 3ccfd60b
// "v" value. 1byte
2a
// a0-0x80=160-128=32 bytes=64 chars= "r" VALUE
a0 fce2a70cde55dc86a203d2387469c36da00e9a9f3536b867f6761c314b1f1423
// a0-0x80=160-128=32 bytes=64 chars= "s" VALUE
a0 7b85742fd48a687b8daa097d1fb9d4b5135de6deb5b6fd16dd0f28d6c28727b6