Document avalon options in ASIC-README

ASIC-README

@@ -61,9 +61,48 @@ a preinstalled version of cgminer as part of the flash firmware, based on the
 most current cgminer version so no configuration should be necessary. It is
 possible to plug a USB cable from a PC into the Avalon device and use the
 --avalon-options copying the command as used by the internal router used by the
-Avalon. However since the Avalon code still currently uses the old serial usb
-interface and is being rewritten to use direct USB, it is prudent to not be
-dependent on this command long term, assuming it will go away.
+Avalon. eg:
+
+--avalon-options 115200:24:10:45:282
+
+The values are baud : miners : asic count : timeout : frequency.
+
+Baud:
+The device is pretty much hard coded to emulate 115200 baud so you shouldn't
+change this.
+
+Miners:
+Most Avalons are 3 module devices, which come to 24 miners. 4 module devices
+would use 32 here.
+
+Asic count:
+Virtually all have 10, so don't change this.
+
+Timeout:
+This is how long the device will work on a work item before accepting new work
+to replace it. It should be changed according to the frequency (last setting).
+It is possible to set this a little lower if you are trying to tune for short
+block mining (eg p2pool) but much lower and the device will start creating
+duplicate shares.
+
+Sample settings for different frequencies (last 2 values):
+43:300
+45:282
+47:270
+50:256
+
+Frequency:
+This is the clock speed of the devices. Only specific values work, 256, 270,
+282 (default) and 300.
+
+If you use the full curses based interface with Avalons you will get this
+information:
+AVA 0: 22/ 46C  60%/2400R
+
+The values are:
+ambient temp / highest device temp  set fan % / lowest detected fan RPM.
+
+Use the API for more detailed information than this.
 
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