NEC PD754244 Network Card User Manual


 
CHAPTER 4 INTERNAL CPU FUNCTION
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Users Manual U10676EJ3V0UM
RBE Register Bank
(2) Register bank select register (RBS)
The register bank select register specifies a register bank to be used as general-purpose registers. It can
select bank 0 to 3.
RBS is set by the SEL RBn instruction (n = 0-3).
When the RESET signal is asserted, RBS is initialized to 0.
Table 4-7. RBE, RBS, and Register Bank Selected
RBS
3210
000××Fixed to bank 0
1 0000Selects bank 0
0 1 Selects bank 1
1 0 Selects bank 2
1 1 Selects bank 3
× = dont care
Fixed to 0