+ comment about buffer channels

py393/x393_sens_cmprs.py

@@ -1474,7 +1474,12 @@ class X393SensCmprs(object):
         @param histogram_height_m1 - one less than window height. If 0 - use frame bottom margin (end of VACT)
         @param reset_afi            Reset AFI multiplexer when initializing
 
+        2018/01/02: the buffer sizes and addresses can be read from sysfs.
+                    /sys/devices/soc0/elphel393-mem@0/buffer_address_circbuf_chn0..3, buffer_address_raw_chn0..3
+                    buffer_pages_circbuf_chn0..3,   buffer_pages_raw_chn0..3, page size is 4096
+
         @param circbuf_chn_size - circular buffer size for each channel, in bytes
+
         @param verbose - verbose level
         @return True if all done, False if exited prematurely by  exit_step
         """