Calculator User Manual

3-1
Central Processing Unit
This chapter describes the main components of the central processing unit
(CPU). First, this chapter describes three fundamental sections of the CPU
(see Figure 3–1):
Input scaling section
Multiplication section
Central arithmetic logic section
The chapter then describes the auxiliary register arithmetic unit (ARAU), which
performs arithmetic operations independently of the central arithmetic logic
section. The chapter concludes with a description of status registers ST0 and
ST1, which contain bits for determining processor modes, addressing pointer
values, and indicating various processor conditions and arithmetic logic re-
sults.
Topic Page
3.1 Input Scaling Section 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Multiplication Section 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Central Arithmetic Logic Section 3-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Auxiliary Register Arithmetic Unit (ARAU) 3-12. . . . . . . . . . . . . . . . . . . . .
3.5 Status Registers ST0 and ST1 3-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 3