King Billion Electronics Co., Ltd

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HE83005

HE80000 SERIES

July 28, 2003

5

V3.4

This specification is subject to change without notice. Please contact sales person for the latest version before use.

SXI

SXI

SXO

SXO

Crystal Osc.

RC Osc.

Mask Option

Description

MO_SXTAL

0: RC Oscillator.

1: Crystal Oscillator.

MO_SCKN

0: Slow clock enable

1: Slow clock disable

With two clock sources available, the system can switch among operation modes of Normal, Slow, Idle,

and Sleep modes by the setting of OP1 and OP2 registers as shown in tables below to suit the needs of

application such as power saving, etc.

OP1

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Field

DRDY

STOP

SLOW

INTE

T2E

T1E

Z

C

Mode

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Reset

1

0

0

0

0

0

-

-

OP2

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Field

IDLE

PNWK

TCWK

-

-

Mode

R/W

R

R

-

-

-

-

-

Reset

0

-

-

-

-

-

-

-

6. General Purpose I/O

The PRTC[7..0] and PRTD[7..0] are dedicated general purpose I/O port. All the I/O ports are

bi-directional and non-tristate output structure. The output has weak sourcing (50µA) and stronger

sinking (1mA) capability and each can be configured as push-pull or open-drain output structure

individually by mask option.

When the I/O port is used as input, the weakly high sourcing can be used as weakly pull-up. Open drain

can be used if the pull-up is not required and let the external driver to drive the pin. Please note that a

floating pad could cause more power consumption since the noise could interfere with the circuit and

cause the input to toggle. A ‘1’ needs to be written to port first before reading the input data from the I/O

pin. If the PMOS is used as pull-up, care should be taken to avoid the constant power drain by DC path

between pull-up and external circuit.

The input port has built-in Schmidt trigger to prevent it from chattering. The hysteresis level of Schmidt

trigger is 1/3*VDD.