XDN ↔ WXDN Bridge

Wrap XDN into BEP-20 WXDN on Binance Smart Chain, or unwrap back. No wallet connection required — send coins directly to the generated address.

Wrap XDN → WXDN

XDN

DigitalNote

→

WXDN

Binance Smart Chain

Amount to send (XDN)MAX

XDN

Your BSC address (receives WXDN)

Email for confirmation (optional)

We only send one confirmation email when your WXDN is delivered. No other emails.

A unique XDN deposit address is generated for your session (30-minute window). Send XDN to that address — bridge maps it to your BSC destination via sub-address database. No OP_RETURN memo needed.

Bridge ID —

30:00 remaining Deposit window — send XDN before expiry

Session expired. This deposit address is no longer monitored.

Your unique XDN deposit address

—

Send exactly — XDN to this address. This address is mapped exclusively to your BSC destination — no memo required.

Session: —

You send—

Bridge fee (0.5%)—

WXDN you receive—

BSC destination—

Awaiting XDN deposit

Send XDN to the address above within 30 minutes. Bridge monitors all sub-addresses in real-time.

15 block confirmations (~10 min)

Daemon matches incoming tx to your session by sub-address lookup. Waits for 15 XDN blocks for finality.

Bridge operator mints WXDN

Contract owner calls mint() on the WXDN contract. Fee deducted. Net WXDN minted to your BSC address.

WXDN delivered

WXDN arrives in your BSC wallet.

Amount to send (WXDN)MAX

WXDN

Your XDN destination address (receives XDN)

Email for confirmation (optional)

We only send one confirmation email when your XDN is delivered. No other emails.

A unique BSC deposit address is generated for your session (30-minute window). Send WXDN to that address — no MetaMask connection, no approve(), no BNB gas required from you.

Bridge ID —

30:00 remaining Deposit window — send WXDN before expiry

Session expired. This deposit address is no longer monitored.

Your unique WXDN deposit address (BSC)

—

Send your WXDN to this BSC address within 30 minutes. Standard token transfer — no contract approval needed.

Session: —

You send—

Bridge fee (0.5%)—

XDN you receive—

XDN destination—

Awaiting WXDN deposit

Send WXDN to the BSC address above within 30 minutes. Plain token transfer — no approval needed.

12 BSC block confirmations (~36s)

Daemon matches received WXDN to your XDN destination via sub-address database lookup.

WXDN burned from reserve pool

Daemon burns equivalent WXDN to keep total XDN + WXDN supply constant.

XDN released to your address

Custodian wallet sends XDN via sendtoaddress RPC.

Your balances

XDN

DigitalNote chain

—

WXDN

Binance Smart Chain

—

XDN lookup xdn-explorer.com

WXDN lookup BSC RPC

Recent bridge activity live

Contract & Specifications

Technical reference for the XDN↔WXDN bridge. The WXDN contract is live on Binance Smart Chain mainnet.

WXDN Contract (BSC Mainnet)

Contract address0xbea2576f400b070c7cdf11d1cbb49de0c84e3bcf

Token nameWrapped DigitalNote (WXDN)

StandardBEP-20 (ERC20Mintable, ERC20Burnable, Ownable)

Solidity version^0.7.0 (OpenZeppelin)

Decimals18

Mint authorityowner() — Ownable. The bridge operator BSC address must be set as contract owner to mint.

Minting capNo on-chain cap enforced. finishMinting() can permanently seal minting if called — do not call this.

Burn functionburn(uint256) / burnFrom(address, uint256) — available. Bridge uses reserve pool burn, not per-user burn, to reduce gas costs.

BSCScanView on BSCScan ↗

Bridge Parameters

Exchange rate1 XDN = 1 WXDN (1:1, enforced by reserve pool)

Bridge fee0.5% (deducted from gross amount before mint/release)

Minimum amount1,000 XDN / 1,000 WXDN per session

Session timeout30 minutes from deposit address generation. Expired sessions are de-monitored.

XDN confirmations15 blocks (~10 minutes)

BSC confirmations12 blocks (~36 seconds)

Deposit methodBIP-32 HD sub-address per session. No OP_RETURN memo. No wallet connection required.

XDN Chain

Address version byte0x1E → D-prefix addresses (mainnet)

WIF key version0xCB (mainnet)

Block time~60 seconds

Custodian sub-addressesBIP-32 child keys derived from custodian HD wallet (m/44'/0'/0'/0/N)

XDN daemon RPCJSON-RPC on 127.0.0.1:18094. Bridge calls listreceivedbyaddress, gettransaction, sendtoaddress.

Security Model

Double-mint preventionSQLite UNIQUE constraint on (xdn_txid, vout). Each XDN deposit can only create one wrap job.

Supply balanceTotal XDN + WXDN = constant. Wrap: XDN locked in custodian, WXDN minted from reserve. Unwrap: WXDN burned from reserve, XDN released.

Key isolationBRIDGE_CUSTODIAN_WIF: read at startup to derive D-address only. XDN daemon handles signing. BRIDGE_BSC_OPERATOR_KEY: signs raw BSC transactions in daemon memory — never stored on disk.

Session expirySub-addresses are de-monitored after 30 minutes if no deposit detected. Expired deposits after timeout require manual recovery contact.

Operator key rotationOwnable.transferOwnership() on the WXDN contract rotates mint authority without redeployment.

How it works — Wrap (XDN → WXDN)

Sub-address generated

Backend derives BIP-32 child key at index N from custodian HD wallet. Stores {sub_N → BSC_destination, amount, expiry_30min} in SQLite.

User sends XDN

Standard XDN send from any wallet. XDN daemon (unmodified xdn-wallet) detects incoming tx via listreceivedbyaddress. Matched to session by sub-address DB lookup.

15 confirmations

Daemon polls gettransaction every 30s. After 15 blocks, job moves to confirmed. Amount converted to 18-decimal WXDN wei. 0.5% fee deducted.

Mint WXDN

BSC operator signs raw EIP-155 tx calling mint() on the WXDN contract. Contract validates caller is owner(). Net WXDN minted to user BSC address. Confirmation email sent if provided.

How it works — Unwrap (WXDN → XDN)

BSC sub-address generated

Backend derives child BSC address from operator HD wallet at index N. Stores {bsc_sub_N → XDN_destination, amount, expiry_30min} in SQLite.

User sends WXDN

Standard WXDN token transfer to BSC sub-address. No MetaMask required, no approve(), no BNB gas from user. Operator hot wallet polls BSC token transfers to all its sub-addresses.

12 BSC confirmations

Daemon detects WXDN receipt via eth_getLogs on BSC. Matches to XDN destination by sub-address DB lookup. Burns equivalent WXDN from reserve pool. 0.5% fee retained.

XDN released

Daemon calls sendtoaddress on XDN RPC. Net XDN sent from custodian wallet to user D-address. Confirmation email sent if provided. Bridge session closed.