Library /sys$common/syshlp/ncphelp.hlb SET, CIRCUIT, MAXIMUM BUFFERS number  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Applies to DDCMP CONTROL circuits.  It specifies the maximum
 number of buffers from a common buffer pool that the tributary
 can use.  If you do not set this parameter, there is no common
 buffer pool and the higher level will explicitly supply the
 buffers.  Number must be a decimal integer in the range up to 254
 or the keyword UNLIMITED.