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How PDC works

A PDC transaction is a proof that value moved, plus the minimum data a wallet needs to find its own outputs. Observers can check the proof. They cannot read the wallet fields.

Addresses

The published address is for people you give it to. It does not appear on the chain as the receiver of a transfer.

Prefix	Kind	Source constant
`Px`	Standard address	`CURRENCY_PUBLIC_ADDRESS_BASE58_PREFIX` (`0x1989`)
`iP`	Integrated address, carries a payment id	`CURRENCY_PUBLIC_INTEG_ADDRESS_BASE58_PREFIX`
`aPx`	Auditable address	`CURRENCY_PUBLIC_AUDITABLE_ADDRESS_BASE58_PREFIX`
`aiPX`	Auditable integrated address	`CURRENCY_PUBLIC_AUDITABLE_INTEG_ADDRESS_BASE58_PREFIX`

An integrated address lets a sender attach a payment id without a separate field. An auditable wallet can hand a tracking seed to a reviewer. That seed is for the reviewer you choose. It is not published by a normal transfer.

The wallet recovery phrase is 24 words. simplewallet prints it with show_seed. The spend key and the view key are separate secrets (spendkey, viewkey).

The privacy stack

Stealth outputs. Each output pays a one-time address derived for that transfer.
d/v-CLSAG. The signature proves you own one input in a ring. It does not tell an observer which one. Decoys default to 10 and become 15 after hard fork 4.
Commitments and Bulletproofs+. Pedersen commitments hide the value. The bpp range proof shows the hidden values are consistent.
Blinded asset ids. A wallet transfer does not announce whether the output is native PDC or a token issued on the chain.
Zarcanum. After height 100, proof of stake uses Zarcanum. The chance of producing a stake block follows the coins you stake. The amount stays sealed.

Transaction version 2 is the post-hard-fork-4 version. From that fork, a transaction has at least 2 outputs. Inputs are capped at 256, mainly by the asset surjection proof. Outputs are capped at 2,000.

Fees and unlock

The default fee and the minimum fee are both 0.01 PDC (TX_DEFAULT_FEE and TX_MINIMUM_FEE). Coinbase outputs unlock after 10 blocks (CURRENCY_MINED_MONEY_UNLOCK_WINDOW). A coinstake must also be at least 10 blocks old before it can stake.

Blocks and emission

get_base_block_reward returns PREMINE_AMOUNT at height 0 and CURRENCY_BLOCK_REWARD at every later height. Those values are 0 and 1 PDC. There is no supply cap in this function.

Difficulty is adjusted over a window of 720 blocks, with a lag of 15 and a cut of 60 timestamps. The proof-of-work target and the proof-of-stake target are 120 seconds each. DIFFICULTY_TOTAL_TARGET is their sum divided by 4, which is 60 seconds. CURRENCY_BLOCKS_PER_DAY is therefore 1,440.

Proof-of-stake blocks cannot run forever in a row. BLOCK_POS_STRICT_SEQUENCE_LIMIT is 20, so the longest allowed run is 21 sequential proof-of-stake blocks.

Hard forks

Mainnet heights are fixed in currency_config.h. Hard fork 5 is not scheduled: its height is set far beyond any practical chain length.

Fork	Active after height	What changes for a user
1	20	Early consensus rules
2	40	Early consensus rules
3	60	Block version moves forward
4 Zarcanum	100	Mandatory 15 decoys, minimum coin age 10, transaction version 2, Zarcanum stake, confidential assets in their post-fork form
5	not scheduled	Present in the source, not active on mainnet

The comments next to the mainnet heights record historical timestamps from the code's lineage. On this network the heights are the rules that matter: fork 4 is the one a wallet feels, and it is already active once the chain passes block 100.

Mempool and reorgs

A transaction can sit in the pool for 345,600 seconds (4 days) before the lifetime rule drops it. Alternative blocks are kept for a limited time: the live window is about 2 hours of blocks (CURRENCY_ALT_BLOCK_LIVETIME_COUNT), and the stored set is capped at 43,200 entries.