![NEC V850/SA1 mPD703015 Preliminary User'S Manual Download Page 28](http://html.mh-extra.com/html/nec/v850-sa1-mpd703015/v850-sa1-mpd703015_preliminary-users-manual_249279028.webp)
CHAPTER 1 INTRODUCTION
28
1.6.2 On-chip units
(1) CPU
The CPU uses five-stage pipeline control to enable single-clock execution of address calculations, arithmetic
logic operations, data transfers, and almost all other instruction processing.
Other dedicated on-chip hardware, such as the multiplier (16 bits
×
16 bits
→
32 bits) and the barrel shifter (32
bits) help accelerate processing of complex instructions.
(2) Bus control unit (BCU)
The BCU starts a required external bus cycle based on the physical address obtained by the CPU. When an
instruction is fetched from external memory space and the CPU does not send a bus cycle start request, the
BCU generates a prefetch address and prefetches the instruction code. The prefetched instruction code is
stored in an instruction queue.
The V850/SA1 is equipped with BV
DD
and BV
SS
as power supply pins for the bus interface. These provide an
external interface using a lower voltage level compared to the V
DD
and V
SS
pins.
(3) ROM
This consists of a 128-Kbyte mask ROM or a 256-Kbyte flash memory mapped to the address space starting at
00000000H. Both types of memory are accessed by the CPU in one clock cycle when an instruction is fetched.
(4) RAM
This consists of a 4-Kbyte RAM mapped to the address space starting at FFFFE000H if the device includes
mask ROM, or an 8-Kbyte RAM mapped to the address space starting at FFFFD000H if the device includes flash
memory. RAM can be accessed by the CPU in one clock cycle.
(5) Interrupt controller (INTC)
This controller handles hardware interrupt requests (NMI, INTP0-INTP6) from on-chip peripheral hardware and
external hardware. Eight levels of interrupt priorities can be specified for these interrupt requests, and
multiplexed servicing control can be performed for interrupt sources.
(6) Clock generator (CG)
The clock generator includes two types of oscillators, each for main system clock (f
XX
) and for subsystem clock
(f
XT
), generates five types of clocks (f
XX
, f
XX
/2, f
XX
/4, f
XX
/8, and f
XT
), and supplies one of them as operating clocks
for the CPU (f
cpu
).
Summary of Contents for V850/SA1 mPD703015
Page 2: ...2 MEMO ...
Page 100: ...100 MEMO ...
Page 144: ...144 MEMO ...
Page 200: ...200 MEMO ...
Page 328: ...328 MEMO ...
Page 356: ...356 MEMO ...
Page 358: ...358 MEMO ...
Page 368: ...368 MEMO ...
Page 374: ...374 MEMO ...
Page 382: ...382 MEMO ...