HT82M9BE/HT82M9BA

Rev. 1.80

23

December 22, 2008

Clock Control Register

- SCC

There is a system clock control register implemented to select the clock used in the MCU. This register consists of USB

clock control bit (USBCKEN), second suspend mode control bit (SUSPEND2) and system clock selection (SCLKSEL).

Bit No.

Label

Read/Write

Option

Functions

0~2

PF0~PF2

R/W

¾

Reserved, must set to

²0².

3

PF3

R/W

USBCKEN

USB clock control bit. When set to

²1², indicates a USBCK ON,

else USBCK OFF. The default value is

²0².

4

PF4

R/W

SUSPEND2

This bit is used to reduce power consumption in the suspend

mode. In the normal mode this bit must be cleared to zero(De-

fault=

²0²). In the HALT mode this bit should be set high to re-

duce power consumption and LVR with no function. In the USB

mode this bit cannot be set high.

5

PF5

R/W

¾

Reserved, must set to

²0².

6

PF6

R/W

SCLKSEL

System clock 6MHz or 12MHz option, when working on exter-

nal oscillator mode. The default value is

²0².

0: Operating at external 12MHz mode

1: Operating at external 6MHz mode

The default value is

²0².

7

PF7

R/W

PS2_flag

This flag is used to show that the MCU is in PS2 mode (Bit=1).

This bit is R/W by FW and will be cleared to zero after power-on

reset. The default value is

²0².

SCC (0X1C) Register

Table High Byte Pointer for Current Table Read

- TBHP

Bit No.

Label

Read/Write

Option

Functions

4~0

PGC4~PGC0

R/W

¾

Store current table read bit12~bit8 data

TBHP (0X1F) Register

Options

No.

Option

1

WDT clock source: RC (system/4) (default: T1)

2

WDT clock source: enable/disable for normal mode (default: disable)

3

PA0~PA7 ,PB4, PB7 wake-up by bit (PA2, PA3 both wake-up by falling or rising edge)

(default: non wake-up)

4

PA0~PA7 pull-high by bit (default: pull-high)

5

PB pull-high by bit (default: pull-high)

6

PC pull-high by nibble (default: pull-high)

7

LVR enable/disable (default: enable)

8

PA0~PA3, PB2, PB3 pull-low by bit (default: non pull-low 30k

W)

9

²CLR WDT², 1 or 2 instructions

10

TBHP enable/disable (default: disable)

11

PA output mode (CMOS/NMOS/PMOS) by bit (default: CMOS)