Quote from: stellan0r on August 04, 2013, 04:14:48 PM

Quote from: DobZombie on August 03, 2013, 02:41:51 PM

So can somebody link me to the 14mhz and the 16mhz crystal oscillator that can be used? can I just buy any old 4 pin crystal?

do I have to upgrade the power?

I'm a little thrown off by some of the specifics of the thread, and I want to get in start soldering (I'm awesome with a soldering iron

)

I would really like to try that, too

http://www.conrad.de/ce/de/Search.html?search=smd+quarz+oszillator+5+x+3.2+x+1+mm

just go straight for the top one, any other mods needed? Wink

(ok ok.. that one https://secure.reichelt.de/Oszillatoren-SMD-Keramikgehaeuse/XO53-16-00000/3/index.html?;ACTION=3;LA=446;ARTICLE=85031;GROUPID=4004;artnr=XO53+16%2C00000)

That oscillator should work fine, it's pin compatible, voltage and size is correct.

Quote from: GilesBathgate on August 04, 2013, 07:08:26 PM

Quote from: Bluestreak66 on August 03, 2013, 07:29:50 AM

Correct me if I'm wrong but doesn't usb communication send parity check bits along with the data? It would seem that the silabs chip would handle some error checking on the usb layer but I may be wrong. I haven't dealt much with the software side of things when it comes to bitcoin mining. It seems like as long as error rates are less than 1% them nobody seems to bother reducing them further, I don't think I would bother either. However it would be good to know where these errors are coming from.

Its not really a USB connection, its a rs232 serial connection. rs232 can support parity, but this is just for error detection. What I would do, if I had my hands on the firmware would be to modify it to send the 4 bytes of nonce, 3 times in a row (so total of 12 bytes). This would serve as error checking (the 3 nonce values didn't match) and error correction (take the two nonce's that do match). There are more complex schemes for checking and correction codes, that potentially use less bytes, but for the sake of 12 bytes this is about as simple as you can get.

Are you talking about the communication from the micro to the silabs chip? That is rs232. If your talking from the silabs chip to the pc that is an emulated rs232 connection. Error checking is done per the usb protocol. Each USB transaction has a Token Packet, Data Packet and Status Packet. With those three things it can transfer the data, check the data for errors and correct errors that happened during that transaction. Error correction does not work 100% of the time. I can pull the firmware off the micro if your interested in looking at it.