ht82a523r Holtek Semiconductor Inc., ht82a523r Datasheet - Page 22

• Manufacturer Part Number: ht82a523r
• Description: Ht82a523r -- Usb 2.0 Full Speed 8-bit Otp Mcu
• Manufacturer: Holtek Semiconductor Inc.

The FIFO size of each FIFO is 8 byte (FIFO0), 8 byte (FIFO1), 8 byte (FIFO2) and 128 byte (FIFO3), and total of 152
bytes.
URD (bit7 of the USC) is USB reset signal control function definition bit.
The USR (USB endpoint interrupt status register) register is used to indicate which endpoint is accessed. The endpoint
request flags (EP0IF, EP1IF, EP2IF and EP3IF) are used to indicate which endpoints are accessed. If an endpoint is ac-
cessed, the related endpoint request flag will be set to 1 and the USB interrupt will occur (if the USB interrupt is en-
abled, the corresponding 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. 1.30
Bit No.
Bit No.
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
RESUME
RMWK
EEP0I
EEP1I
EEP2I
EEP3I
SUSP
URST
EP0IF
EP1IF
EP2IF
EP3IF
Label
V33O
Label
URD
PLL
R/W
R/W
R/W
R/W 0/1: Turn-off/on V33O output
R/W 0: Turn-on the PLL (default mode); 1: turn-of the PLL
R/W
R/W
R/W
R/W
R/W
R/W
R/W Control the endpoint 0 interrupt (1=enabled; 0=disable).
R/W Control the endpoint 1 interrupt (1=enabled; 0=disable).
R/W Control the endpoint 2 interrupt (1=enabled; 0=disable).
R/W Control the endpoint 3 interrupt (1=enabled; 0=disable).
R
R
Read only, USB suspend indication. When this bit is set to 1 (set by SIE), it indicates
that the USB bus enters the suspend mode. The USB interrupt is also triggered on any
changes of this bit.
USB remote wake-up command. It is set by the MCU to force the USB host leaving the
suspend mode. Set RMWK bit to 1 to enable remote wake-up. When this bit is set to
is accepted by the SIE.
USB reset indication. This bit is set/cleared by USB SIE. When the URST is set to 1 ,
this indicates that a USB reset has occurred and a USB interrupt will be initialized.
USB resume indication. When the USB leaves the suspend mode, this bit is set to 1
(set by SIE). This bit will appear for 20ms, waiting for the MCU to detect it. When the
RESUME is set by SIE, an interrupt will be generated to wake-up the MCU. In order to
detect the suspend state, MCU should set the USBCKEN and SUSP2 (in the SCC reg-
ister) to enable the SIE detect function. The RESUME will be cleared while the SUSP
is set to 0 . When MCU detects the SUSP, the RESUME (which causes MCU to
wake-up) should be remembered and token into consideration.
Undefined bit, read as 0
USB reset signal control function definition
1: USB reset signal will reset the MCU
0: USB reset signal cannot reset the MCU
When this bit is set to 1 (set by SIE), it indicates that 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 SIE), it indicates that 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 SIE), it indicates that the endpoint 2 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 SIE), it indicates that the endpoint 3 is accessed and a
USB interrupt will occur. When the interrupt has been served, this bit should be cleared
by firmware.
1 , a 2 s delay for clearing this bit to 0 is needed to insure that the RMWK command
USC (20H) Definitions
USR (21H) Definitions
22
Function
Function
HT82A523R
May 13, 2008