HP -16C Owner's Handbook Manual page 72

70 Section 6: Memory and Storage
Example: Store 3 in Ry In order to have a storage register as
high as Rjy4 available for data storage, the word size must be at
most four bits long (203 bytes/0.5 byte = 406 registers.) To be able
to store a number as large as 326 in the Index register, however, the
word size must be larger. (The Index register must be used to
address any register higher than Rj,, which is Ri.) To store 3 in
Ry will therefore require two manipulations of word size. Assume
that the calculator is set to word size 4.
Keystrokes Display ([STATUS]: 2-04-0000)
0 Sets a large word size
(64).
326 326 d
326 d Stores 326,,in Ry.
4 6 d 406 registers of 4 bits
each are now available.
3[sTo]((i)] 3 d Stores3in Ry
BSP 0 d Clearsdisplay.
3 d Recalls contents of Ryo.