HP 3000 III Series Manual page 193

System Microcode
Table 5-4. Function Field Code Definitions
1-----.---~---·-·--l-·-~--·--T~·------·-----·-~---~-·--'-'---"---'-~
I
I ~
Fie Id
I I
I
Label and Name
I
Cbde
I
Description
I
I I I I
------_._--_._~~ --·---·I-------~-~·_-----_·_----------I
ADD 11111
I
The content of the R-Bus Register
I
is added to the content of the S-
I
Bus Register and the result is
placed on the T-Bus.
ADDO 11011
(Add-Enable Over-
flow)
AND 00111
BNDT 01101
(Bo unds Tes t)
CAD 01110
(Complement and
Add)
The content of the R-Bus Register
is added to the content of the S-
Bus Register and the result is
placed on the T-Bus.
The content of the R-Bus Register
is logically "anded" with the con-
tent of the S-Bus Registe r and the
result is placed on the T-Bus.
The Function field code BNDT is us-
ed to perform a bounds test of an
address. Execution of this code
results in the content of the R-Bus
Register minus the content of the
S-Bus Register being placed on the
T-Bus. If RRZ, RLZ, LRZ, or LLZ is
specified, then BNDT does a "CAD"
instead of a "SUB". The R- and S-
Bus fields are coded so that this
result is a negative number (CARRY=
0) if a bounds violation occurs.
If the CPU is not operating in the
priviledged mode (STATUS (0) = 0),
and a bounds violation occurs, a
microjump to ROM address 0003 is
executed. If no violation has oc-
curred (CARRY = 1) or the CPU is
operating in the priviledged mode
(STATUS (0) = 1), the next microin-
struction will be executed in the
usual manner.
The content of the R-Bus Register
is added to the one's complement of
the content of the S-Bus Register
and the result is placed on the T-
Bus. If the S-Bus Register con-
tains all zeros, CAD results in the
- - - ~ ~ . _ .
__
.~-- -~-- ---,-,~-----------,_.--,---.-,--",----
5-13