ht82k95e Holtek Semiconductor Inc., ht82k95e Datasheet - Page 21

• Manufacturer Part Number: ht82k95e
• Description: Ht82k95e/ht82k95a -- Usb Multimedia Keyboard Encoder 8-bit Mcu
• Manufacturer: Holtek Semiconductor Inc.

The definitions of the USB/PS2 status and control register (USC; 1AH) are as shown.
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 and EP2IF) are used to indicate which end-
points are accessed. If an endpoint is accessed, the related endpoint request flag will be set to 1 and the USB inter-
rupt will occur (if the 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 0 .
Rev. 2.00
Bit No.
Bit No.
3, 6
0
1
2
3
4
5
6
7
0
1
2
4
5
7
RESUME
USB_flag
PS2DAO
PS2CKO
PS2DAI
PS2CKI
RMWK
EP0IF
EP1IF
EP2IF
Label
SUSP
URST
Label
SPS2
SUSB
R/W
R/W
R/W
R/W
R/W
R/W
R/W The PS2 function is selected when this bit is set to 1 . (Default= 0 )
R/W The USB function is selected when this bit is set to 1 . (Default= 0 )
R/W
W
W
W
R
R
R
R
Read only, USB suspend indication. When this bit is set to 1 (set by SIE), it indi-
cates the USB bus enters suspend mode. The USB interrupt is also triggered on any
changes of this bit.
USB remote wake up command. It is set by MCU to force the USB host leaving the
suspend mode. When this bit is set to 1 , 2 s delay for clearing this bit to 0 is
needed to insure the RMWK command is accepted by SIE.
USB reset indication. This bit is set/cleared by USB SIE. This bit is used to detect
which bus (PS2 or USB) is attached. When the URST is set to 1 , this indicates that
a USB reset has occurred (the attached bus is USB) and a USB interrupt will be ini-
tialized.
USB resume indication. When the USB leaves the suspend mode, this bit is set to
RESUME is set by the SIE, an interrupt will be generated to wake-up the MCU. In or-
der to detect the suspend state, the MCU should set the USBCKEN and clear
SUSP2 (in SCC register) to enable the SIE detecting function. The RESUME will be
cleared while the SUSP is going 0 . When the MCU is detecting the SUSP, the RE-
SUME (wakes-up the MCU ) should be remembered and taken into consideration.
Read only, USBD-/DATA input
Read only, USBD+/CLK input
Data for driving the USBD-/DATA pin when working under 3D PS2 mouse function.
(Default= 1 )
Data for driving the USBD+/CLK pin when working under 3D PS2 mouse function.
(Default= 1 )
When this bit is set to 1 (set by the SIE), it indicates the endpoint 0 is accessed and
a USB interrupt will occur. When the interrupt has been served, this bit should be
cleared by firmware.
When this bit is set to 1 (set by the SIE), it indicates the endpoint 1 is accessed and
a USB interrupt will occur. When the interrupt has been served, this bit should be
cleared by firmware.
When this bit is set to 1 (set by the SIE), it indicates the endpoint 2 is accessed and
a USB interrupt will occur. When the interrupt has been served, this bit should be
cleared by firmware.
Reserved
This flag is used to show the MCU is in USB mode. (Bit=1)
This bit is R/W by FW and will be cleared to 0 after power-on reset. (Default= 0 )
1 (set by SIE). This bit will appear 20ms waiting for the MCU to detect. When the
USC (1AH) Register
USR (1BH) Register
21
Function
Function
HT82K95E/HT82K95A
April 16, 2008