HP HP-11C - Storage Register Arithmetic

Section 2: Memory Stack, LAST X, and Data Storage 39
LAST X registers. (To clear a single data storage register, store zero
in that register.)
Storage Register Arithmetic
([+], (5], [x], [£)) n (storage register arithmetic). Uses the
number in the displayed X-register to perform arithmetic upon the
contents of a specified storage register n. The key sequence is
followed by an arithmetic function key, followed in turn by the
register address (0 through 9).* The result of any storage register
arithmetic operation is placed in the specified data storage register.
Storage
Stack Registers
If.. T+ and..Ro |
z R
Y= R I:
X R3 |7
represent the current status of the memories, executing 1
results in:
T and Rj E:‘
Z> R,
Y= R, ]
X Ry —
The same numbers Contents of R, changed
in the stack from k to (k X d).
registers.
*Storage register arithmetic can be performed in R through Rg using indirect
addressing, which is covered in section 9, The Index Register. Storage register
arithmetic cannot be performed in Ry.