ethereumcommonwealth/bursadex

BURSA TRADING MANUAL

ens://bursadex.eth

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TO SELL ERC20 TOKENS ON BURSA:

1. Approve your ERC20 tokens.

DO NOT TRANSFER TOKENS TO BURSA! Just execute approve() method on contract of the token you want to trade. You can check the tradable amount of a token by calling balanceApprovedForToken() method on BURSA contract.

NOTE: The amounts of tokens are represented the way they are stored on the blockchain. That means, if you have 10 tokens, and the token has 18 decimals, the amount of tokens stored will be 10 + 1e18 = 10000000000000000000 (10 + 18 zeroes appended). Prices are always stored with 18 decimals, regardless token's decimals.

2. There are two ways to sell tokens on BURSA:

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2.1. Place sell order on BURSA (FREE)

1. Call willsellFindSpot(token), token address as argument.
2. Use returned value spot in the next call.
3. Execute willsell(amount, token, price_each, spot):
   • amount - amount of tokens to buy
   • token - token address
   • price_each - price for one token, followed by 18 zeroes
   • spot - the place in storage to save our order, returned from the previous call
4. Wait until someone fills your order! Trade event will be fired.

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2.2. Fill existing sell order (0.0001 ether fee, 1st TRADE FOR FREE)

1. Call findBestBid(token, min_trade_amount): Arguments:

   • token - token address
   • min_trade_amount - (optional) minimum order amount (in wei)

   Returns:

   • order - order id, use it in the next call
   • volume - maximum amount of tokens this order can buy
   • price - price of one token

2. Use returned order and price in the next call.

3. Execute sell(amount, token, min_price_each, order, frontend_refund):

   • amount - amount of tokens to buy
   • token - token address
   • max_price_each - (optional, recommended) price for one token
   • price from the previous call
   • order - the order index returned from the previous call
   • frontend_refund - (optional) can be used by frontend developers

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TO BUY ERC20 TOKENS ON BURSA:

1. There are few ways to deposit ether to BURSA contract.

• Sending it to the contract;
• Calling deposit() method;
• Adding value to willbuy() or buy() method.

2. There are two ways to buy tokens on BURSA:

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2.1. Place buy order on BURSA (FREE)

1. Call willbuyFindSpot(token), token address as argument.

2. Use returned value spot in the next call.

3. Execute willbuy(amount, token, price_each, spot):

   • amount - amount of tokens to buy
   • token - token address
   • price_each - price for one token, followed by 18 zeroes
   • spot - the place in storage to save our order, returned from the previous call

4. Wait until someone fills your order! Trade event will be fired.

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2.2. Fill existing buy order (0.0001 ether FEE, 1st TRADE FOR FREE!)

1. Call findBestAsk(token, min_trade_amount).

   Arguments:

   • token - token address
   • min_trade_amount - (optional) minimum order amount (in wei)

   Returns:

   • order - order id, use it in the next call
   • volume - maximum amount of tokens this order can buy
   • price

2. Use returned order and price in the next call.

3. Execute buy(amount, token, min_price_each, order, frontend_refund):

   • amount - amount of tokens to buy
   • token - token address
   • min_price_each - (optional, recommended) price for one token, price from the previous call
   • order - the order index returned from the previous call
   • frontend_refund - (optional) can be used by frontend developers

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HANDLE YOUR TRADING ACCOUNT:

Withdraw your money using withdraw() method.

CANCELLING YOUR ORDER:

You can always cancel your own order by executing it from the address it was placed. It's free and costs little gas. Uncovered orders may be cancelled automatically in the process of trading.

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FEES:

Placing orders is free on BURSA. Using methods buy() or sell() is free for any address for the 1st time. Trading amounts < 0.001 ether is free. BURSA has fixed fee of 0.0001 ether for trading amounts over 0.001 ether (except for the first trade). One can refund 0.0003 ether to frontend_refund address in buy() and sell() methods.

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BURSA on Ethereum mainnet

BURSA on ropsten

BURSA abi:

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MINTABLE TEST TOKEN on ropsten

MINTABLE TEST TOKEN abi:

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