UPD784915AGF View Datasheet(PDF) - NEC => Renesas Technology

Part Name

Description

Manufacturer

UPD784915AGF

16-BIT SINGLE-CHIP MICROCONTROLLERS

NEC => Renesas Technology 

µPD784915A, 784916A

3. INTERNAL BLOCK FUNCTIONS

3.1 CPU Registers

3.1.1 General-purpose registers

The µPD784916A has eight banks of general-purpose registers. One bank consists of sixteen 8-bit general-

purpose registers. Two of these 8-bit registers can be used in pairs as a 16-bit register. Four of the 16-bit general-

purpose registers can be used to specify a 24-bit address in combination with an 8-bit address expansion register.

These eight banks of general-purpose registers can be selected by software or context switching function.

The general-purpose registers, except for the address expansion registers V, U, T, and W, are mapped to the

internal RAM.

Figure 3-1. Configuration of General-Purpose Registers

A (R1)

X (R0)

AX (RP0)

B (R3)

C (R2)

BC (RP1)

R5

R4

RP2

R7

R6

RP3

V

R9

R8

VP (RP4)

VVP (RG4)

U

R11

R10

UUP (RG5)

UP (RP5)

T

D (R13)

E (R12)

DE (RP6)

TDE (RG6)

W

H (R15)

L (R14)

HL (RP7)

WHL (RG7)

( ): absolute name

8 banks

Caution

Although R4, R5, R6, R7, RP2, and RP3 can be used as X, A, C, B, AX, and BC registers,

respectively, by setting the RSS bit of PSW to 1, do not use this function. The function of the

RSS bit is planned to be deleted from the future models in the 78K/IV Series.

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