Hedera (HBAR)

Sign Hedera transactions and messages. The device signs a CryptoTransfer built from balanced transfers[] (native HBAR) or tokenTransfers[] (HTS tokens). A Hedera accountId (0.0.x) is assigned at account creation and is not derivable from the key.

Field	Value
coinType	3030
keyPath	m/44'/3030'/<accountIdx>'
amount unit	tinybar (1 HBAR = 1e8)
chainId	hedera:mainnet/slip44:3030

Supported Methods

Method	Supported
getAddress	✓
signTransaction	✓
signMessage	✗
signTypedData	✗

Requirements

Minimum firmware for each method. The two models are on different version lines, so DCENT Biometric Wallet and DCENT X are listed separately (the numbers are not comparable across models). Below this the request returns the firmware-update error (5005) and the bridge prompts to update.

Method	DCENT Biometric Wallet	DCENT X
getAddress	2.19.3 or higher	1.0.0 or higher
signTransaction	2.19.3 or higher	1.0.0 or higher

getAddress — account address

Retrieves the account public key for a chainId + keyPath. Because a Hedera accountId (0.0.x) is assigned at account creation and is not derivable from the key, the device returns the derived public key in parameter — resolve the matching accountId from a mirror node before building a CryptoTransfer. Hedera has no address variants, so addressFormat does not apply.

Field	Type	Required	Source	Description
chainId	string	Required	App	CAIP-19 — hedera:mainnet/slip44:3030
keyPath	string	Required	App	BIP-44, default m/44'/3030'/0'

Request

await dcent.getAddress({
  chainId: 'hedera:mainnet/slip44:3030',
  keyPath: "m/44'/3030'/0'"
})

Response

Field	Type	Description
address	string	The account public key derived from keyPath. Hedera does not return a 0.0.x accountId from the device — use this public key to look up the accountId on a mirror node.

{
  "header": {
    "version": "1.0",
    "status": "success"
  },
  "body": {
    "command": "getAddress",
    "parameter": {
      "address": "302a30…"
    }
  }
}

info

The returned value is the account's public key, not a 0.0.x address. Resolve the accountId from a mirror node before populating transfers[].accountId / tokenTransfers[].accountId.

signTransaction <CryptoTransfer>

Variant — native HBAR transfer

Field	Type	Required	Source	Description
type	string	Required	App	Always "CryptoTransfer"
transfers[].accountId	string	Required-Real	Wallet	Real Hedera account 0.0.x — sender side must be the device account (not key-derivable)
transfers[].amount	number	Required	App	tinybar; negative = debit (sender), positive = credit (recipient); all entries sum to 0
memo	string	Optional	App	Transaction memo (empty string allowed)
maxTransactionFee	number	Required	App	Fee cap in tinybar
transactionValidDuration	number	Optional	App	Validity window in seconds (e.g. 120)

Request:

await dcent.sign({
  method: 'signTransaction',
  chainId: 'hedera:mainnet/slip44:3030',
  payload: {
    keyPath: "m/44'/3030'/0'",
    transaction: {
      "type": "CryptoTransfer",
      "transfers": [
        {
          "accountId": "0.0.587690",
          "amount": -100000000
        },
        {
          "accountId": "0.0.587690",
          "amount":  100000000
        }
      ],
      "memo": "",
      "maxTransactionFee": 100000000,
      "transactionValidDuration": 120
    }
  }
})

Response

Field	Type	Description
header.status	string	"success" on completion; an error envelope otherwise
body.command	string	"signTransaction"
body.parameter.signature	string	The broadcast-ready serialized signed Hedera transaction (signed CryptoTransfer protobuf bytes), not a bare signature — submit it directly to a Hedera node

{
  "header": {
    "status": "success"
  },
  "body": {
    "command": "signTransaction",
    "parameter": {
      "signature": "<signed tx bytes>"
    }
  }
}

Variant — HTS token transfer

info

Token model: form-D descriptor (same pattern as TRON / Havah / Stacks). Always send a compact token descriptor instead of raw tokenTransfers[] (see the variant below) — the bridge builds the CryptoTransfer envelope itself, no node timestamp or registry lookup required. See Core Concepts → Token descriptors.

HTS (Hedera Token Service) transfers carry tokenTransfers[] instead of transfers[]. There is no native HBAR movement (no transfers field). Amounts are in the token's own base units — for SAUCE (6 decimals) 1.5 SAUCE = 1500000, not tinybar.

Field	Type	Required	Source	Description
type	string	Required	App	Always "CryptoTransfer"
tokenTransfers[].tokenId	string	Required	App	HTS token id 0.0.x — a registered mainnet token resolves display metadata automatically; an unregistered token still signs, but use the token descriptor variant below instead of raw tokenTransfers[]
tokenTransfers[].accountId	string	Required-Real	Wallet	Real Hedera account 0.0.x; recipient must have associated the token first
tokenTransfers[].amount	number	Required	App	Token base units; negative/positive pair summing to 0
memo	string	Optional	App	Transaction memo
maxTransactionFee	number	Required	App	Fee cap in tinybar

Request:

await dcent.sign({
  method: 'signTransaction',
  chainId: 'hedera:mainnet/slip44:3030',
  payload: {
    keyPath: "m/44'/3030'/0'",
    transaction: {
      "type": "CryptoTransfer",
      "tokenTransfers": [
        {
          "tokenId": "0.0.731861",
          "accountId": "0.0.587690",
          "amount": -1500000
        },
        {
          "tokenId": "0.0.731861",
          "accountId": "0.0.587690",
          "amount":  1500000
        }
      ],
      "memo": "",
      "maxTransactionFee": 100000000
    }
  }
})

Response

Field	Type	Description
header.status	string	"success" on completion; an error envelope otherwise
body.command	string	"signTransaction"
body.parameter.signature	string	The broadcast-ready serialized signed Hedera transaction (signed CryptoTransfer protobuf bytes carrying the HTS transfer), not a bare signature — submit it directly to a Hedera node

{
  "header": {
    "status": "success"
  },
  "body": {
    "command": "signTransaction",
    "parameter": {
      "signature": "<signed tx bytes>"
    }
  }
}

Variant — HTS form-D descriptor

Send a compact token descriptor instead of raw tokenTransfers[]. The bridge builds the balanced two-leg CryptoTransfer (negative sender / positive recipient) from { contract, to, amount } and signs — no HTS registry lookup, no node timestamp. from (or sender / owner_address) is read-only and identifies the debit leg — omitting it fails with -32602. amount is a base-unit number (not rescaled by decimals).

payload.transaction:

{
  "token": {
    "contract": "0.0.731861",
    "to": "0.0.587690",
    "amount": 1500000,
    "decimals": 6,
    "symbol": "SAUCE"
  },
  "from": "0.0.587690",
  "maxTransactionFee": 100000000
}

Field	Type	Required	Description
token.contract	string	Required	HTS token id 0.0.x; unregistered tokens allowed
token.to	string	Required	Recipient 0.0.x (must have associated the token)
token.amount	number	Required	Base-unit number; not rescaled by decimals
token.decimals	number	Optional	Display metadata only
token.symbol	string	Optional	Display metadata only
from	string	Required-Real	Device Hedera account that signs (read-only; sender / owner_address also accepted). Omitting it fails with -32602

Variant — unsignedTx (blind-sign passthrough)

Send a pre-built, frozen Hedera Transaction serialized to bytes (hex) under unsignedTx. The device blind-signs the bytes as-is — this is the only fully self-contained signTransaction form for Hedera; it covers any operation (TokenCreate / Mint / Burn / TransferTransaction / …), not just transfers. Missing or malformed bytes return -32602.

Field	Type	Required	Source	Description
unsignedTx	hex string	Required-Real	App	Serialized, frozen Hedera Transaction bytes (hex) built outside the device

Request

await dcent.sign({
  method: 'signTransaction',
  chainId: 'hedera:mainnet/slip44:3030',
  payload: {
    keyPath: "m/44'/3030'/0'",
    transaction: {
      "unsignedTx": "0a9d012a9a010a95010a160a080880e2cfaa06100012080800100018aaef2318..."
    }
  }
})

signMessage Not supported — returns -32601

Field	Type	Required	Source	Description
keyPath	string	Required	Wallet	Signing path, default m/44'/3030'/0'
message	string	Required	App	Message bytes to sign

Request:

await dcent.sign({
  method: 'signMessage',
  chainId: 'hedera:mainnet/slip44:3030',
  payload: {
    keyPath: "m/44'/3030'/0'",
    message: '<bytes>'
  }
})

Response

Field	Type	Description
header.status	string	"success" on completion; an error envelope otherwise
body.command	string	"signMessage"
body.parameter.signature	string	The raw signature over the supplied message bytes (not a serialized transaction)

{
  "header": {
    "status": "success"
  },
  "body": {
    "command": "signMessage",
    "parameter": {
      "signature": "<signature>"
    }
  }
}

Supported transaction types

Hedera has two signing paths:

• Structured operation — pass a typed object and the bridge builds + signs the bytes: TransferTransaction (HBAR + HTS transfers), TokenAssociate / TokenDissociate.
• Blind-sign passthrough — build and freeze the transaction yourself (Hedera SDK) and pass the serialized unsignedTx bytes; the device blind-signs any operation (TokenCreate / Mint / Burn / etc.). Matches v1 getHederaSignedTransaction.

info

The structured ops the bridge builds are limited to transfer + associate / dissociate. Everything else (TokenCreate / Mint / Burn / Freeze / …, AccountCreate / Update) goes through blind-sign passthrough — the device shows raw bytes rather than a parsed summary.

Common Mistakes

danger

Using a key-derived address as accountId — a Hedera accountId (0.0.x) is assigned at account creation, not derived from the key. Replace transfers[].accountId / tokenTransfers[].accountId with your real device Hedera account. Unbalanced transfers — the negative (sender) and positive (recipient) amounts must sum to exactly 0. Wrong amount unit for tokens — HTS tokenTransfers[].amount is in token base units (SAUCE = 6 decimals), not tinybar. Recipient has not associated the token — an HTS transfer fails unless the recipient ran TokenAssociate for that token first.

• signTransaction
• signMessage