# bitcoin-spv-utils

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## API

  - [`bits2buf(Number bits)`](#)
  - [`buf2bits(Buffer buf)`](#)
  - [`getMaxTarget()`](#)
  - [`getTarget(Buffer first, Buffer last)`](#)
  - [`verifyHeader(Buffer header, Buffer previous, Object target [, Boolean isTestnet = false])`](#)
  - [`verifyHeaders(Buffer[] headers, Buffer previous, Object target [, Boolean isTestnet = false]`](#)

#####`bits2buf(Number bits)` -> `Buffer`

Unpack bits.

#####`buf2bits(Buffer buf)` -> `Number`

Pack bits.

#####`getMaxTarget()` -> `{bits: Number, buf: Buffer}`

Return max target. (bits -- 0x1d00ffff, hex -- 00000000ffff0000000000000000000000000000000000000000000000000000)

#####`getTarget(Buffer first, Buffer last)` -> `{bits: Number, buf: Buffer}`

Calculate target of next chunk.

#####`verifyHeader(Buffer header, ?Buffer previous, Object target [, Boolean isTestnet = false])` -> `Boolean`

Verify given header.

#####`verifyHeaders(Buffer[] headers, ?Buffer previous, Object target [, Boolean isTestnet = false]` -> `Boolean`

Verify given headers.

## License

Code released under [the MIT license](LICENSE).


Useful functions for Simple Payment Verification. 

bitcoin-spv-utils

Useful functions for Simple Payment Verification

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bitcoin-spv-utils