-configures a list of inclusive ranges of those registers to expose. Number 0
-indicates the first custom register, whose abstract command number is 0xc000.
-This command must be executed before `init`.
+configures individual registers or register ranges (inclusive) that shall be exposed.
+Number 0 indicates the first custom register, whose abstract command number is 0xc000.
+For individually listed registers, a human-readable name can be optionally provided
+using the @code{n=name} syntax, which will get @code{custom_} prepended to it. If no
+name is provided, the register will be named @code{custom<n>}.
+
+@example
+# Expose one RISC-V custom register with number 0xc010 (0xc000 + 16)
+# under the name "custom16":
+$_TARGETNAME expose_custom 16
+
+# Expose a range of RISC-V custom registers with numbers 0xc010 .. 0xc018
+# (0xc000+16 .. 0xc000+24) under the names "custom16" through "custom24":
+$_TARGETNAME expose_custom 16-24
+
+# Expose one RISC-V custom register with number 0xc020 (0xc000 + 32) under
+# user-defined name "custom_myregister":
+$_TARGETNAME expose_custom 32=myregister
+@end example