This README contains extended details about FPGA mining with cgminer ModMinerQuad (MMQ) ------------------ The mining bitstream does not survive a power cycle, so cgminer will upload it, if it needs to, before it starts mining You must make sure you have an approriate firmware in your MMQ Read here for official details of changing the firmware: http://wiki.btcfpga.com/index.php?title=Firmware The basics of changing the firmware are: Join the 2 left pads of the "RESET" pad with wire and the led will dim Without dicsonnecting the "RESET", join the 2 left pads of the "ISP" pad with a wire and it will stay dim Release "RESET" then release "ISP" and is should still be dim Unplug the USB and when you plug it back in it will show up as a mass storage device Linux: (as one single line): mcopy -i /dev/disk/by-id/usb-NXP_LPC134X_IFLASH_ISP000000000-0:0 modminer091012.bin ::/firmware.bin Windows: delete the MSD device file firmware.bin and copy in the new one rename the new file and put it under the same name 'firmware.bin' Disconnect the USB correctly (so writes are flushed first) Join and then disconnect "RESET" and then plug the USB back in and it's done Best to update to one of the latest 2 listed below if you don't already have one of them in your MMQ The current latest different firmware are: Latest for support of normal or TLM bitstream: http://btcfpga.com/files/firmware/modminer092612-TLM.bin Latest with only normal bitstream support (Temps/HW Fix): http://btcfpga.com/files/firmware/modminer091012.bin The code is currently tested on the modminer091012.bin firmware. This comment will be updated when others have been tested Bitforce (BFL) -------------- --bfl-range Use nonce range on bitforce devices if supported This option is only for bitforce devices. Earlier devices such as the single did not have any way of doing small amounts of work which meant that a lot of work could be lost across block changes. Some of the "minirigs" have support for doing this, so less work is lost across a longpoll. However, it comes at a cost of 1% in overall hashrate so this feature is disabled by default. It is only recommended you enable this if you are mining with a minirig on p2pool. C source is included for a bitforce firmware flash utility on Linux only: bitforce-firmware-flash.c Using this, you can change the bitstream firmware on bitforce singles. It is untested with other devices. Use at your own risk! To compile: make bitforce-firmware-flash To flash your BFL, specify the BFL port and the flash file e.g.: sudo ./bitforce-firmware-flash /dev/ttyUSB0 alphaminer_832.bfl It takes a bit under 3 minutes to flash a BFL and shows a progress % counter Once it completes, you may also need to wait about 15 seconds, then power the BFL off and on again If you get an error at the end of the BFL flash process stating: "Error reading response from ZBX" it may have worked successfully anyway. Test mining on it to be sure if it worked or not. You need to give cgminer about 10 minutes mining with the BFL to be sure of the MH/s value reported with the changed firmware - and the MH/s reported will be less than the firmware speed since you lose work on every block change. Icarus (ICA) ------------ There are two hidden options in cgminer when Icarus support is compiled in: --icarus-options Set specific FPGA board configurations - one set of values for all or comma separated baud:work_division:fpga_count baud The Serial/USB baud rate - 115200 or 57600 only - default 115200 work_division The fraction of work divided up for each FPGA chip - 1, 2, 4 or 8 e.g. 2 means each FPGA does half the nonce range - default 2 fpga_count The actual number of FPGA working - this would normally be the same as work_division - range is from 1 up to 'work_division' It defaults to the value of work_division - or 2 if you don't specify work_division If you define fewer comma seperated values than Icarus devices, the last values will be used for all extra devices An example would be: --icarus-options 57600:2:1 This would mean: use 57600 baud, the FPGA board divides the work in half however only 1 FPGA actually runs on the board (e.g. like an early CM1 Icarus copy bitstream) --icarus-timing Set how the Icarus timing is calculated - one setting/value for all or comma separated default[=N] Use the default Icarus hash time (2.6316ns) short Calculate the hash time and stop adjusting it at ~315 difficulty 1 shares (~1hr) long Re-calculate the hash time continuously value[=N] Specify the hash time in nanoseconds (e.g. 2.6316) and abort time (e.g. 2.6316=80) If you define fewer comma seperated values than Icarus devices, the last values will be used for all extra devices Icarus timing is required for devices that do not exactly match a default Icarus Rev3 in processing speed If you have an Icarus Rev3 you should not normally need to use --icarus-timing since the default values will maximise the MH/s and display it correctly Icarus timing is used to determine the number of hashes that have been checked when it aborts a nonce range (including on a LongPoll) It is also used to determine the elapsed time when it should abort a nonce range to avoid letting the Icarus go idle, but also to safely maximise that time 'short' or 'long' mode should only be used on a computer that has enough CPU available to run cgminer without any CPU delays (an active desktop or swapping computer would not be stable enough) Any CPU delays while calculating the hash time will affect the result 'short' mode only requires the computer to be stable until it has completed ~315 difficulty 1 shares 'long' mode requires it to always be stable to ensure accuracy, however, over time it continually corrects itself When in 'short' or 'long' mode, it will report the hash time value each time it is re-calculated In 'short' or 'long' mode, the scan abort time starts at 5 seconds and uses the default 2.6316ns scan hash time, for the first 5 nonce's or one minute (whichever is longer) In 'default' or 'value' mode the 'constants' are calculated once at the start, based on the default value or the value specified The optional additional =N specifies to set the default abort at N 1/10ths of a second, not the calculated value, which is 112 for 2.6316ns To determine the hash time value for a non Icarus Rev3 device or an Icarus Rev3 with a different bitstream to the default one, use 'long' mode and give it at least a few hundred shares, or use 'short' mode and take note of the final hash time value (Hs) calculated You can also use the RPC API 'stats' command to see the current hash time (Hs) at any time The Icarus code currently only works with an FPGA device that supports the same commands as Icarus Rev3 requires and also is less than ~840MH/s and greater than 2MH/s If an FPGA device does hash faster than ~840MH/s it should work correctly if you supply the correct hash time nanoseconds value The timing code itself will affect the Icarus performance since it increases the delay after work is completed or aborted until it starts again The increase is, however, extremely small and the actual increase is reported with the RPC API 'stats' command (a very slow CPU will make it more noticeable) Using the 'short' mode will remove this delay after 'short' mode completes The delay doesn't affect the calculation of the correct hash time