UPDATE (November 23, 2013): The instructions provided below are for an older version of CGMiner, version 3.1.1. Please refer to CGMiner’s instructions and readme files when downloading more recent versions of this miner. I am no longer mining on Windows. I have not tested newer versions.
STEP 1: Download and install CGMiner.
A windows binary can be found here: http://ck.kolivas.org/apps/cgminer/.
STEP 2: Download and install this driver.
The driver can be found here: http://www.silabs.com/products/mcu/Pages/USBtoUARTBridgeVCPDrivers.aspx
This driver will allow you to “see” your Block Erupters in the Printers and Devices section of the PC’s Control Panel.
STEP 3: Plug in the USB miners.
If you have more than one Erupter, consider that they consume about 560 milliamps. You will most likely need a powered USB hub. I have 4 Erupters and they work very nicely as pictured in a Plugable 7 Port USB 3.0 Hub with 4A Power Adapter (VIA VL812 Chipset – USB 2.0 compatible) from Amazon.com
STEP 4: Note down the COM Numbers for each Device.
- In Windows 7, go to Control Panel
- Click on Printers and Devices
- You should see USB devices similar to what is shown below:
Silicon Labs CP210x USB to UART Bridge (COM3)
Silicon Labs CP210x USB to UART Bridge (COM4)
Silicon Labs CP210x USB to UART Bridge (COM5)
Silicon Labs CP210x USB to UART Bridge (COM6)
STEP 5: Create a Desktop Shortcut.
To launch cgminer, create a shortcut with a target command line that looks like this:
C:\cgminer\cgminer-nogpu.exe -o [pool]:[port] -u [username].[worker] -p [password] --icarus-options 115200:1:1 --icarus-timing 3.0=100 -S //./COM3 -S //./COM4 -S //./COM5 -S //./COM6
Notice that pool, port, username, worker and password are private credentials you provide for your pool worker.
Notice that COM3, COM4, COM5, COM6 are the COM numbers for my four miners. Yours will be different depending on what is reported in your Device Manager. You would need as many of these in your target line as you have miners.
STEP 6: Launch CGMiner.
Launch CGMiner from the shortcut and you should see something like this:
Interesting Notes: I wanted to see how much power these consume. Using a Kill a Watt device, I measured that the USB hub and the four miners together consume 0.19 amps and 13.2 watts while mining. With only one Erupter in the hub, the Kill a Watt reports 0.05 amps and 3.4 to 3.6 watts. As mentioned in the forum, the Kill-a-watt is not precise for milliamps, but it does show that these devices consume a lot less power than say, GPU miners.