sha256 - (bitcoin) Calculate hash from getwork function
How can I code a Bitcoin JSON-RPC "getwork" request in Java?
To arms Bitcoin community! Help us to complete this mining installation for the Zürich MoneyMuseum. We are not asking for funds. Only your expertise needed! 20$ tip if you give us the relevant clue to solve or mitigate our main problem. Nice pictures of the exhibition inside as well…
Edit: A big thank you to all people who helped us we can now mine true pps with diff1! The people in this thread which have helped most have been awarded. I want to mention also the operator of btcmp.com denis2342 and Luke-Jr. Actually looking at the miner screen in the Linux terminal helped a lot ;-). The pool constantly resigned to stratum with variable difficulty. We can now mine true pps with diff1. Getwork with long polling seems to be default after disabling stratum... We will probably post again, when there is a video of the installation in action... Again many thanks. Learned a lot. Edit: Thank you for all the answeres so far! We will try different things now and report back. Tip bounty will be distrubuted as soon as we found out what finally does the trick. Ths could take a few days. The offerd tip will be distributed and very likeley a few others as well. First of all, let me tell you that the Bitcoin Exhibition at the Zürich MoneyMuseum is most likely the biggest and most diverse of it’s kind. Please read more about the museum and the exhibition below. Help us solve the following problem we experience with our “Muscle Powered Proof of Work” installation: Me and a friend have invested a lot of time to build an installation for the Museum. It is basically a 10GHash/s miner and RapberryPi which is powered by a hand generator (Maxon DC motor with planetary gear). Here are some pictures of the installation, although not entirely put together yet. There are still some changes planned. https://www.dropbox.com/sh/0qcvl3wu4romhnt/AAAYF08lnVAy6W6KEepE7e2Ua?dl=0 Now let’s get to the core of our problem: We are mining at the getwork diff1 pool btcmp.com as it is a true pps pool with getwork diff1. The visitors in the museum can power the generator for 2-3min and see directly how many Satoshis the "network" (actually pool but we don't want to confuse the visitors to much at that point) has given the museum for their work. This all works well so far but one problem remains. Sometimes the pool does not get a share from us for more than 40 seconds or even more than 60 in some cases. I have calculated that with 8.4 GHash/s we should find a share about every 0.5 seconds in average (diff1). I think when the pool gets a share it gets all the hashes as it then accounts for several Satoshis. Statistically we get per minute what we should get in theory. We would very much like to lower the time between the accepted shares by the pool, however. This would help to make the overall experience much smoother for the visitors. Please look at this screenshot from MinePeon and answer some questions: https://www.dropbox.com/s/lb1jei4trc9kqe5/MinePeonScreenshot.png?dl=0 We see that we get a lot of diff1 hashes. However, only 11 shares/packages have been accepted. The Is there a possibility to set the miner SW so it submits to the pool as soon as a share is found? It seems to send them in packages which sometimes have 4-5 seconds in between but sometimes a much as 80 seconds. I would like to submit packages of hashes much more often. How can this be influenced? What exactly are the Getworks (GW)? What exactly are the Accepted ones (Acc)? This is where the TipBounty is. Help us to get a better Acc/diff1 ratio. Best would be 1:1. What exactly are the rejected ones (Rej)? What exactly are the discarded ones (Disc)? What exactly are the difficulty one hashes (diff1)? Now some of these questions seem very very basic but it is important for us to understand what these are and how we can influence these. We have a 1:1 correlation between the Acc and the pool side acknowledgement of shares/packages. So whenever the MinePeon shows one more for this value the pool value for last submitted share goes to “moments ago”. Does the miner SW have a setting where we can set after how many diff1 hashes a package of hashes is sent to the pool? If no, do you have another idea why so few are sent? Ideally we would set it so the diff1 hashes are sent every 5 seconds or so, probably even more often. Is stratum with fixed diff1 possible? If so, would it be better to use stratum? Are there critical settings if we should know of? (we have tried --request-diff and --no-submit-stale) We are using BFGMiner on MinePeon if that matters. We could switch to CGMiner if that would help. Any help is very much appreciated. The museum is doing a great job explaining Bitcoin basics. We had special focus on interactive learning and have several things to underline this. I hope to hear back from you so we can improve our installation. Please don't hesitate to ask if you have further questions. We are both not mining experts. Thanks for reading and AMA. SimonBelmond Current features of the Bitcoin exhibition at the Zürich MoneyMuseum: Current Features:
Life screen with various stats/charts/parameters/transactions…
Muscle powered PoW: Hand generator with 5v and 3.5-5A output, Raspberry Pi, MinePeon, 5x Antminer U2+ plus a screen to show the hash-rate at the pool and/or in MinePeon web interface. This screen will not be hand powered. This installation will complement their coining die (go to 1:27 to see what I mean).
The Bitcoin mining evolution (CPU, GPU, FPGA, ASIC)
A few short (2-3 minutes) interviews.
Other wallets, Trezor, PiperWallet
ATM Prototype, functional
PiperWallet to use.
Casascius and other physical Bitcoins, Wallets (also some commemorative coins), Paper wallet like one out of the first Bitcoin (A)TM ever
12 Picture tours
Bitcoin for beginners
Debunking 13 Bitcoin myths
What you definitely have to know
The history of Bitcoin
Bitcoin und traditional forms of money
Alternatives to Bitcoin
Citations about Bitcoin
How do I open an account?
How do I get Bitcoin?
Bitcoin community and economy
Bitcoin as a platform
I see this as a good opportunity for Bitcoin, so let’s embrace it. I am especially excited to compare the traditional forms of money which used proof of work to the new money which also uses proof of work. I think in that context it will be much easier for the visitors to value this concept. A lot of schools and other groups book guided tours at the museum. It is open on every Friday from December 05. On. Entry is free of charge. Edit:Markdown, typos
P2Pool Error messages within shell window (win 10 pro)
Hi all, Newbie trying to run my own P2Pool node for VTC and within the shell window periodically I start seeing the below error msg's in 15 second blurts, then it goes back to mining normal then all the sudden I will start seeing these error messages again. Error Message in P2Pool shell window: Error getting work from bitcoind: Traceback (most recent call last): File "twisted\internet\defer.pyc", line 653, in _runCallbacks File "twisted\internet\defer.pyc", line 1357, in gotResult File "twisted\internet\defer.pyc", line 1299, in _inlineCallbacks File "twisted\python\failure.pyc", line 393, in throwExceptionIntoGenerator --- --- File "p2pool\util\deferral.pyc", line 41, in f File "twisted\internet\defer.pyc", line 1299, in _inlineCallbacks File "twisted\python\failure.pyc", line 393, in throwExceptionIntoGenerator File "p2pool\bitcoin\helper.pyc", line 47, in getwork File "twisted\internet\defer.pyc", line 1299, in _inlineCallbacks File "twisted\python\failure.pyc", line 393, in throwExceptionIntoGenerator File "p2pool\util\jsonrpc.pyc", line 126, in _http_do twisted.web.error.Error: 500 Internal Server Error Worker VvstnCT7shwVwg1JBh3du41dGMkq6V2gC1 submitted share more than once! Does anyone know what it means? I'm generating VTC coins, but get these messages when the coins are being mined. Please help this newbie!
i found this very handy. stolen from here A: The number of Accepted shares R: The number of Rejected shares HW: The number of HardWare errors WU: The Work Utility defined as the number of diff1 equivalent shares / minute AVA 0: 23C/ 47C 2280R | 77.10G/83.20Gh/s | A:120029 R:0 HW:2295 WU:1162.5/m Each column is as follows: Temperature (if supported) Fanspeed (if supported) A 5 second exponentially decaying average hash rate An all time average hash rate The number of accepted shares The number of rejected shares The number of hardware erorrs The Work Utility defined as the number of diff1 equivalent shares / minute The cgminer status line shows: TQ: 1 ST: 1 SS: 0 DW: 0 NB: 1 LW: 8 GF: 1 RF: 1 TQ is Total Queued work items. ST is STaged work items (ready to use). SS is Stale Shares discarded (detected and not submitted so don't count as rejects) DW is Discarded Work items (work from block no longer valid to work on) NB is New Blocks detected on the network LW is Locally generated Work items GF is Getwork Fail Occasions (server slow to provide work) RF is Remote Fail occasions (server slow to accept work)
Stratum is a pooled mining protocol. The stratum protocol was extended to support pooled mining as a replacement for obsolete getwork protocol. The goal is to make a reliable stratum mining server for a wide range of coins. After 1-5 min have this issue: 2012-12-24 07:30:55,834 INFO proxy jobs. # C extension for midstate not available. Using default implementation instead. 2012-12-24 07:30:55,835 WARNING proxy mining_... If Bitcoin-SE is the incorrect place to post it, I apologize in advance; I'm new to SE and this was my best guess. I'm attempting, in order to better understand how Bitcoin mining works, to code a simple Bitcoin CPU miner in Java, which I have some but not much experience with. +1 on the --no-getwork / coinbase addy + stale share submit I use your software every day, using it less and less because of inability to solo on my rigs. Needs to be incorporated asap especially considering profits are down so far and it's becoming less and less feasible to throw money away at a pool when there's a significant chance for 100% The hash calculation is documented at Block hashing algorithm.Start there for the relatively simple basics. The basic data structures are documented in Protocol specification - Bitcoin Wiki.Note that the protocol definition (and the definition of work) more or less assumes that SHA-256 hashes are 256-bit little-endian values, rather than big-endian as the standard implies.
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