QmNd46viDJi6rSkNBrgx3Jy6KL5qZVyCJDm2kdkA4oCcB2

Location | Action| Object | Time Chrome | Click | Tab Keccak | 1 https://emn178.github.io/online-tools/keccak_256.html | Paste | ContractBalance() | 3 Chrome Output field | Copy | { first 8 characters } | 5 Chrome | Click | Tab Function Signature Database | 13 https://www.4byte.directory/ | Paste | { signature } | 15 https://www.4byte.directory/ | Click | Search | 17 Taskbar | Select| Command Prompt | 24 Command Prompt | Paste | | 33 curl -H "Content-Type: application/json" -d "{""jsonrpc"":""2.0"",""method"":""eth_call"",""params"":[{""from"":"" Taskbar | Select| Chrome | 37 Chrome | Click | Fox icon | 41 MetaMask popup | Click | Account 1 | 42 Taskbar | Click | Command Prompt | 44 Command Prompt | Paste | { account } | 46 Command Prompt | Paste | | 53 "",""to"":"" Taskbar | Select| Chrome | 57 MetaMask popup | Click | Contract Interaction | 60 MetaMask popup - Contract interaction details | Click | To | 62 Taskbar | Click | Command Prompt | 65 Command Prompt | Paste | { contract address } | 68 Command Prompt | Paste | | 74 "",""data"":"" Taskbar | Select| Chrome | 80 Chrome Search Signatures | Copy | {signature} | 90 Taskbar | Click | Command Prompt | 94 Command Prompt | Enter | 0x | 96 Command Prompt | Paste | { signature } | 98 Command Prompt | Paste & enter | | 104 ""},""latest""],""id"":67}" https://ropsten.infura.io Command Prompt - output of curl | Copy | { non zero characters } | 110 Taskbar | Select| Chrome | 113 Chrome | Click | Tab Hexadecimal.. | 115 https://www.binaryhexconverter.com/hex-to-decimal-converter | Paste | {output} | 118 https://www.binaryhexconverter.com/hex-to-decimal-converter | Click | Convert | 121 Chrome | Click | Fox icon | 124 MetaMask popup | Click | Contract interaction | 128 MetaMask popup Contract interaction - Details | Click | Arrow | 130 https://ropsten.etherscan.io/address/... | Click | Contract | 146 Chrome | Click | Tab Hexadecimal.. | 115

The goal is to see how to interact via RPC calls.

Call the function ContractBalance to get the balance of a smart contract (from previous example).

Curl installed, metamask installed and example "Transfer eth with contract-via play" has been run.
Chrome tabs opened with:
- https://emn178.github.io/online-tools/keccak_256.html
- https://www.4byte.directory/
- https://www.binaryhexconverter.com/hex-to-decimal-converter
Cmd window opened
The following contract has been deployed:
pragma solidity >=0.4.0 <0.7.0;
contract TestPay {
    function ContractBalance()            public view returns (uint) { return address(this).balance;  }
    function ()                           external payable           {                                }
    function PayToContract()              public payable             {                                }
    function RequestFromContract()        public                     { msg.sender.transfer(0.1 ether);}
    function Transfer(address payable to) public                     { to.transfer(0.05 ether);       }
}
https://ropsten.etherscan.io/address/0x01848a2cfc60d5b24eb6630f12048c1825059afc

Enter command:
curl -H "Content-Type: application/json" -d "{""jsonrpc"":""2.0"",""method"":""eth_call"",""params"":[{""from"":""0xEA9a7c7cD8d4Dc3acc6f0AaEc1506C8D6041a1c5"",""to"":""0x01848a2cFc60d5b24EB6630F12048C1825059AfC"",""data"":""0x3b668059""},""latest""],""id"":67}" https://ropsten.infura.io

Output:
{"jsonrpc":"2.0","id":67,"result":"0x00000000000000000000000000000000000000000000000002b4c77783338000"}