ANTMINER U3
-----------

The U3 does not support autodetection, so you will want to use --scan-serial to
manually probe it. For example, to scan all devices, you can use:

-S antminer:all --set antminer:chip=BM1382

Additionally, for optimal performance you will need to set voltage, clock, and
timing. Voltage format for the U3 is not documented by the manufacturer, thus
must be provided as hexadecimal configuration codes. Timing is provided in the
number of nanoseconds each hash takes at the given configuration. A
known-working configuration is:

--set antminer:voltage=x800 --set antminer:clock=237.5
--set antminer:timing=0.022421

To set different frequency and voltage settings for multiple U3 miners on a
single BFGMiner process use:

--set antminer@\\.\COM10:voltage=xNNNN

or

--set antminer@/dev/ttyUSB1:voltage=xNNNN

Another option is to program the CP2102 chip so they have unique serial numbers;
this method would avoid problems with the device showing up on different tty/COM
locations after reboot/hotplug:

/cp210x-program -w -F eeprom-content.AntU3-custom.hex --set-product-string='Antminer U3' --set-serial-number=myveryown0001

Then you can use --set antminer@myveryown0001:voltage=xNNNN

COMPAC
------

These USB sticks are based on Bitmain's BM1384 chip, and use the antminer
driver. You can set the clock frequency with

--set compac:clock=200

You can also adjust the clock real-time while the stick is hashing using RPC's pgaset:

bfgminer-rpc "pgaset|0,clock,x0982"
		     |       ^^^^^ hex frequency
		     ^ device number

--set-device|--set <arg> Set default parameters on devices; eg, NFY:osc6_bits=50, bfl:voltage=<value>, compac:clock=<value>