Maxim Integrated 71M6521BE Energy Meter IC Family Software - Manual (Page 106)

71M652X Software User’s Guide
Revision 1.7 TERIDIAN Proprietary 106 of 138
© Copyright 2005-2007 TERIDIAN Semiconductor Corporation
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.
Note: 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.