diff --git a/doc/other.xml b/doc/other.xml
index 9486205..cbac5f3 100644
--- a/doc/other.xml
+++ b/doc/other.xml
@@ -108,27 +108,37 @@ Multiple channels can be read and written simultaneously using the
function
-int comedi_dio_bitfield
+int comedi_dio_bitfield2comedi_t *deviceunsigned int subdeviceunsigned int write_maskunsigned int *bits
+unsigned int base_channel
-Each channel is assigned to a bit in the
+Each channel from base_channel
+to base_channel +
+31 is assigned to a bit in the
write_mask and
bits
-bitfield. If a bit in
+bitfield with bit 0 assigned to channel
+base_channel, bit 1 assigned to channel
+base_channel +
+1, etc. If a bit in
write_mask is set, the
corresponding bit in *bits will
-be written to the corresponding digital output line.
+be written to the digital output line corresponding to the channel given by
+base_channel plus the bit number.
Each digital line is then read and placed into
*bits. The value
of bits in *bits corresponding
to digital output lines is undefined and device-specific. Channel
-0 is the least significant bit in the bitfield;
-channel 31 is the most significant bit. Channels
-higher than 31 cannot be accessed using this method.
+base_channel +
+0 is the least significant bit in the bitfield. No
+more than 32 channels at once can be accessed using this method.
+Warning! Older versions of &comedi;
+may ignore base_channel and treat
+it as 0 unless the subdevice has more than 32 channels.