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Generic special function register overview – Maxim Integrated 71M6513H Power Meter IC Family Software User Manual

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71M651x Software User’s Guide

Generic Special Function Register Overview

All generic SFRs are explained in detail in section 6.3.2.

Register

Symbol

Description

Program status
word

PSW

The PSW contains program status information

Accumulator

ACC

The accumulator register. Mmemonics for instructions involving the accumulator
refer to the accumulator as A.

B register

B

This register is used for multiply and divide operations. It may also be used as a
scratchpad (temporary) register.

Stack pointer

SP

The stack pointer is 8 bits wide and is incremented before data is stored with
PUSH and CALL operations. SP is initialized to 0x07 after reset.

Data pointer

DPL, DPH

Since the DP consists of two bytes (DPH and DPL), it can hold a 16-bit address.
It may be manipulated as a 16-bit register or as two separate 8-bit registers.

Secondary data
pointer

DPL1, DPH1

This register is a second 16-bit data pointer.

Check with the documentation on the compiler used for generating MPU code
whether this pointer is utilized or not.

Data pointer select
register

DPS

This register selects which data pointer is to be used for the current operation.

Port registers

P0, P1, P2

These registers hold bit patters that are written to or read from the DIO ports

Serial data buffer

S0BUF, S1BUF

These registers hold data received from the serial interfaces 0 and 1. Data to be
transmitted via the serial interfaces is written to S0BUF or S1BUF.

Serial port reload
registers

S0RELL, S0RELH,
S1RELL, S1RELH

These register pairs can be used to control the baud rate for the serial ports 0
and 1.

Timer registers

TL0, TL1, TH0,
TH1

These register pairs (TH0/TL0 and TH1/TL1) are the 16-bit counting registers for
timers 0, 1, and 2.

Interrupt control
registers

IP0, IP1, IEN,
IEN0, TMOD,
TCON, T2CON,
SCON, PCON,
IRCON

These registers contain control and status bits pertaining to the interrupt system,
the timers/counters, and the serial port.

Clock control
register

CKCON

The clock control/configuration register. It is used to implement stretch memory
cycles for memory access.

Watchdog timer
reload register

WDTREL

This register holds the reload count for the software watchdog timer

Baud rate
generator selector

WDCON

This register determines whether UART0 is controlled by timer 1 or by the
internal baud rate generator.

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