Test getReserves() on USDC-WETH pair on Ropsen

I have a func to get eth price from uniswap pair USDC-WETH but could’t really test on Ropsten. The pair address is here https://ropsten.etherscan.io/address/0x7cae76c0517ddca4c10bf023b607b4db92114b41#readContract

However, getReserves() will give me (0,0,) for the pair ratio. How can I test a close to mainnet ratio for this pair? Thanks

Emmm, it seems like there is not any reserves in this pair contract, so maybe you can try to add some liquidity and then call this function

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I’m trying to add lidquidity to USDC-WETH pair on Ropsten through Truffle js script but couldn’t quite get it working with this error: Error: IUniswapV2Router02 has not been deployed to detected network (network/artifact mismatch)

module.exports = async function main(callback) {
    try {
        const IUniswapV2Pair = artifacts.require("IUniswapV2Pair");
        const IUniswapV2Factory = artifacts.require("IUniswapV2Factory");
        const IUniswapV2Router01 = artifacts.require("IUniswapV2Router01");
        const IUniswapV2Router02 = artifacts.require("IUniswapV2Router02");

        const uniswapV2Router = await IUniswapV2Router02.deployed('0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D');
        uniswapV2Router.approve('0x7cae76c0517ddca4c10bf023b607b4db92114b41', 1000);

            3, // slippage is unavoidable
            1, // slippage is unavoidable

    } catch (error) {

Do you use truffle to run script or web3.js? I think for truffle, it should be

const uniswapV2Router = await UniswapV2Router02.at('0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D');

And if you use web3.js, it should be:
const uniswapV2Router = await new web3.eth.Contract(Contract_Interface, Contract_address)`
But there is a more easier to do this, you can add liquidity by the website of the Uniswap with the Ropsten network.

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Thank you. I’m using truffle to run the js script. Truffle documentation is quite lacking. How did you know it is UniswapV2Router02.at?

How do I use uniswap front end website on ropsten test net? I only see mainnet.

Just change your network to the Ropsten.