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Timer 2 lsb (tl2), Timer 2 msb (th2), Program status word (psw) – Maxim Integrated Ultra-High-Speed Flash Microcontroller User Manual

Page 43: Timer 2 lsb (tl2) -35, Timer 2 msb (th2) -35, Program status word (psw) -35, Table 4-19. register bank addresses -35, Table 4-19. register bank addresses

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4-35

TL2.7–0
Bits 7–0

Timer 2 LSB. This register contains the least significant byte of Timer 2.

TH2.7–0
Bits 7–0

Timer 2 MSB. This register contains the most significant byte of Timer 2.

CY
Bit 7

AC
Bit 6

F0
Bit 5

RS1, RS0
Bits 4-3

Carry Flag. This bit is set if the last arithmetic operation resulted in a carry (during addition) or a
borrow (during subtraction). Otherwise, it is cleared to 0 by all arithmetic operations.

Auxiliary Carry Flag. This bit is set to 1 if the last arithmetic operation resulted in a carry into (dur-
ing addition) or a borrow (during subtraction) from the high-order nibble. Otherwise, it is cleared to

0 by all arithmetic operations.

User Flag 0. This is a bit-addressable, general-purpose flag for software control.

Register Bank Select 1–0. These bits select which register bank is addressed during register
accesses.

R = Unrestricted read, W = Unrestricted write, -n = Value after reset

Program Status Word (PSW)

7

6

5

4

3

2

1

0

SFR D0h

CY

AC

F0

RS1

RS0

OV

F1

PARITY

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

Table 4-19. Register Bank Addresses

RS1

RS0

REGISTER BANK

ADDRESS

0

0

0

00h – 07h

0

1

1

08h – 0Fh

1

0

2

10h – 17h

1

1

3

18h – 1Fh

OV
Bit 2

F1
Bit 1

PARITY
Bit 0

Overflow Flag. This bit is set to 1 if the last arithmetic operation resulted in a carry (addition), bor-
row (subtraction), or overflow (multiplication or division). Otherwise it is cleared to 0 by all arith-

metic operations.

User Flag 1. This is a bit-addressable, general-purpose flag for software control.

Parity Flag. This bit is set to 1 if the module-2 sum of the 8 bits of the accumulator is 1 (odd parity)
and cleared to 0 on even parity.

R = Unrestricted read, W = Unrestricted write, -n = Value after reset

Timer 2 MSB (TH2)

7

6

5

4

3

2

1

0

SFR CDh

TH2.7

TH2.6

TH2.5

TH2.4

TH2.3

TH2.2

TH2.1

TH2.0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

R = Unrestricted read, W = Unrestricted write, -n = Value after reset

Timer 2 LSB (TL2)

7

6

5

4

3

2

1

0

SFR CCh

TL2.7

TL2.6

TL2.5

TL2.4

TL2.3

TL2.2

TL2.1

TL2.0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

RW-0

Ultra-High-Speed Flash
Microcontroller User’s Guide

Maxim Integrated