HP 3000 III Series Manual page 185

System Microcode
5-10. S-Bus Field
The S-Bus field (bits 0 through 4) selects one
contents to be placed into the S-Bus Register.
code definitions are contained in table 5-3.
5-11. Function Field
of 32 reg is te r
The S-Bus field
The Function field (bits 10 through l4) specifies the function to
be performed by the ALU on the two operands in the R- and S-Bus
Registers or a special function. The Function field code defin-
itions are contained in table
~-4.
5-12. Shift Field
The Shift field (bits 20 through 22) specifies how the T-Bus data
will be shifted. The Shift field code definitions are contained
in table 5-5.
5-13. Store Field
The Store field (bits 5 through 9) selects one of the Store Logic
registers or other destinations outside the CPU for the U-Bus
data.The Store field code definitions are contained in table 5-6.
5-14. Special Field
The Special field (bits 23 through 27) codes perform the various
operations listed in table 5-7.
5-15. MCU Option Field
The MCU Option field (bits 23 through 27) is executed in place of
the Special field when the S-Bus field contains RBR or the Store
field contains BUS, BSPO, BSPl, or SBR. The MCU Option field
codes per form the var ious opera tions Ii sted in table 5-8.
5-16. Skip Field
The Skip field (bits 15 through 19) determines which condition
will be tested for a possible skip and specifies the conditions
under which a JMP or JSB will be executed. The Skip field code
definitions are contained in table 5-9.
5-17. MICRODIAGNOSTICS
The system's microcode also contains diagnostics to test the CPU
registers, Main Memory, I/O channels, magnetic tape subsystem,
and the Asynchronous Terminal Data PCA's. These diagnostics are
executed from the system's Control Panel. Complete information
for these diagnostics is contained in the HP 3000 Computer System
Installat ion Manual, par t no. 30000-90147.
5-5