UPD17P136ACT datasheet(86/292 Pages) NEC

86 / 292 page

CHAPTER 8

GENERAL REGISTER (GR)

The general register (GR) is allocated in data memory. It can therefore be used directly for arithmetic operations

and transferring data.

8.1 GENERAL REGISTER CONFIGURATION

Figure 8-1 shows the configuration of the general register.

As shown in Figure 8-1, 16 nibbles in a single row address in data memory (16

× 4 bits) are used as the general

The register pointer (RP) in the system register is used to indicate which row address is to be used as the general

the general register can be allocated are addresses 0H to 7H of BANK0 and BANK1. However, note that row addresses

0H to 6H of BANK1 are unmounted area and should therefore not be specified as locations for the general register.

8.2 FUNCTIONS OF THE GENERAL REGISTER

The general register can be used in transferring data to and from data memory and in performing arithmetic

operations with data memory within an instruction. In effect, since the general register is data memory, this just means

that operations such as arithmetic operations and data transfer can be performed on and between locations in data

memory. In addition, because the general register is allocated in data memory, it can be controlled in the same manner

as other areas in data memory through the use of data memory manipulation instructions.

UPD17P136ACT Datasheet(PDF) 86 Page - NEC