HP 3000 III Series Manual page 198

System Microcode
Table 5-4. Function Field Code Definitions (Continued)
T--~---l----~----------~-------------'----'I
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Fie 1d
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Label and Name
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Code
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Description
1
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-----------------.----- ------- --------------------------------1
MPAD
(Cont) must be pos it i ve numbe rs upon exe-
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cution of the
MPAD
code. An SRI
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code in the Shift field directs thel
right shift of the T-Bus. The fol-I
lowing algorithm is executed re-
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peatedly to perform a complete mul-
tiply.
T-BUS := R-REG plus S-REG
U-BUS(1:15)
:=
T-BUS(0:14)
U-BUS(O)
:=
ALU carry
If SP3(15)
=
1 then:
BEGIN
S-REG
:=
U-BUS
SP 3 (1 : 15) : = SP 3 ( 0 : 14)
SP
3 ( 0) :
=
T
-BU
S
(15)
END
else:
BEGIN
S-REG{1:15)
:=
S-REG{0:14)
SP3(1:15)
:=
SP3(0:14)
SP3(0)
:=
S-REG(15)
END
After 16-executions of the above
algorithm, the result is a 32-bit
word with the most significant 16
bits in the S-Bus Register and the
least significant 16 bits in the
S P 3 Re g is te r •
PNLR
(Panel Read)
10000 The PNLR Function field code allows
the auxiliary control panel to sel-I
ect and display a CPU register.
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This code appears in the micropro-
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gram during execution of HALT and
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PAUSE routines. When PNLR is exe-
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cuted, the ROM Output Register
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(RORl) and R- and S-Bus fie Id s are
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disabled. The maintenance panel
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5-18