The reg_prgm.doc file gives a brief description of the E1413 register
prorgamming C functions.  1413reg1.c is an example of using the custom.c
program to program the settings of one channel of an option 013 SCP, in
addition to all the other things that custom.c does.  1413reg1.c uses
modified versions of custom.h (custom1.h) and regprgm.h (regprgm1.h).
These modifications are explained in the comments at the top of the
1413reg1.c file.     4-06-95 TC