HT82M9BE/HT82M9BA

Rev. 1.80

22

December 22, 2008

Bit No.

Label

Read/Write

Option

Functions

0~3

PC0~PC3

R/W

¾

I/O (R/W), has pull-high option

4~7

PC4~PC7

R/W

¾

Reserved

PC (16H) Register

This port configures the input or output mode of Port-C

USB/PS2 Status and Control Register

- USC

Bit No.

Label

Read/Write

Option

Functions

0

PE0

R

SUSPEND

USB suspend mode status bit. When 1, indicates that the USB

system entry is in suspend mode.

1

PE1

W

RMOT_WK USB remote wake-up signal. The default value is

²0².

2

PE2

R/W

URST_FLAG USB bus reset event flag. The default value is

²0².

3

PE3

R

RESUME_O

When RESUME_OUT EVENT, RESUME_O is set to

²1².

The default value is

²0².

4

PE4

R

PS2_DAI

USBD-/DATA input

5

PE5

R

PS2_CKI

USBD+/CLK input

6

PE6

W

PS2_DAO

Output for driving USBD-/DATA pin, when working under 3D

PS2 mouse function. The default value is

²1².

7

PE7

W

PS2_CKO

Output for driving USBD-/DATA pin, when working under 3D

PS2 mouse function. The default value is

²1².

USC (0X1A) Register

Endpoint Interrupt Status Register

- USR

The USR (USB endpoint interrupt status register) register is used to indicate which endpoint is accessed and to select

the serial bus (PS2 or USB). The endpoint request flags (EP0IF, EP1IF, EP2IF and EP3IF) are used to indicate which

endpoints are accessed. If an endpoint is accessed, the related endpoint request flag will be set to

²1² and a USB inter-

rupt will occur (If a USB interrupt is enabled and the stack is not full). When the active endpoint request flag is served,

the endpoint request flag has to be cleared to

²0².

Bit No.

Label

Read/Write

Option

Functions

0

PEC0

R/W

EP0IF

When set to

²1², indicates an endpoint 0 interrupt event. Must

wait for the MCU to process the interrupt event and clear this

bit by firmware. This bit must be

²0², then the next interrupt

event will be processed. The default value is

²0².

1

PEC1

R/W

EP1IF

2

PEC2

R/W

EP2IF

3

PEC3

R/W

EP3IF

4

PEC4

R/W

SELPS2

When set to

²1², indicates that the chip is working under PS2

mode. The default value is

²0².

5

PEC5

R/W

SELUSB

When set to

²1², indicates that the chip is working under USB

mode. The default value is

²0².

6

PEC6

R/W

¾

Reserved bit, set to

²0²

7

PEC7

R/W

USB_flag

This flag is used to show that the MCU is in USB 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.

USR (0X1B) Register