block header

[xwen01]

Hi, I'm trying to setup znomp for Fabcoin. I noticed the block header used in znomp follows Zcash protocol, which has 140 bytes block header. The Fabcoin Developer Reference indicates 80-bytes header with 4 bytes nonce. Should I just follow the Fabcoin Developer Reference and change the header and nonce settings in znomp?

Thanks a lot for your help!

[blockchaingate]

Fabcoin is using 140 bytes header which is same as Zcash.

[poroburu]

The Fabcoin header appears to be the same as Zcash except that there is a 4 byte nHeight, and the nReserved is reduced from 32 to 28 bytes.

Although I'm having trouble setting up z-nomp for myself. This is what I am targeting in BlockTemplate.js.

`this.serializeHeader = function(nTime, nonce){
var header = new Buffer(140);
var position = 0;

    console.log('nonce:' + nonce);
    console.log('this.rpcData.bits: ' + this.rpcData.bits);
    console.log('nTime: ' + nTime);
	console.log('this.rpcData.height:', this.rpcData.height.toString(16));
    console.log('this.merkleRootReversed: ' + this.merkleRootReversed);
    console.log('this.prevHashReversed: ' + this.prevHashReversed);
    console.log('this.rpcData.version: ' + this.rpcData.version.toString(16));

    header.writeInt32LE(this.rpcData.version, position += 0, 4, 'hex');
    header.write(this.prevHashReversed, position += 4, 32, 'hex');
    header.write(this.merkleRootReversed, position += 32, 32, 'hex');
	header.writeUInt32LE(this.rpcData.height, position += 32, 4, 'hex');
    header.write('00000000000000000000000000000000000000000000000000000000', position += 4, 28, 'hex'); //hashReserved
    header.write(nTime, position += 28, 4, 'hex');
    header.write(util.reverseBuffer(new Buffer(rpcData.bits, 'hex')).toString('hex'), position += 4, 4, 'hex');
    header.write(nonce, position += 4, 32, 'hex');
    console.log(header.toString('hex'));
	
	
    return header;
};`

But I am getting

1|npm | 2018-08-27 06:57:00 [Pool] [fab coin testnet] (Thread 1) Share rejected: {"job":"cccd","ip":"::ffff:162.219.178.146","worker":"n3nJB5BFk3eEVPocP93yAxQR4KSByxhYKZ.noname","difficulty":0.05,"error":"invalid solution"} 1|npm | nonce:40000000abd4960d042a2e8a2bf344d23627007f000000000000000000000000 1|npm | this.rpcData.bits: 1f0ee3f3 1|npm | nTime: aea0835b 1|npm | this.rpcData.height: 2d10e 1|npm | this.merkleRootReversed: 522d6f7bf7df8122fd80f6793abe244864fbff39aee5b993a0dd88e31c6a63eb 1|npm | this.prevHashReversed: 4301789f491f937c92935a99973c4575482b9c32019c632f466068c4a7e80400 1|npm | this.rpcData.version: 20000000 1|npm | 000000204301789f491f937c92935a99973c4575482b9c32019c632f466068c4a7e80400522d6f7bf7df8122fd80f6793abe244864fbff39aee5b993a0dd88e31c6a63eb0ed1020000000000000000000000000000000000000000000000000000000000aea0835bf3e30e1f0000000000000000000000007f002736d244f32b8a2e2a040d96d4ab00000040 1|npm | Invalid solution: invalid collision length between StepRows 1|npm | X[i] = 05fb6b0a5c270d558701a7920221670f0b510be8c30faaf004fcd20af6a8 1|npm | X[i+1] = 01563707472b058dfd0e0d2c01b7d60d468c072c3e02755c09a7200e9fd3